# tankvolumecalc.com — full inventory > Free tank volume tools built on exact closed-form geometry — circular segments, a piecewise obround model for 275/330 heating-oil tanks, and scaled spherical caps for dished propane heads. No interpolation and no lookup tables. Every unit factor is traced to the standard that defines it (NIST Handbook 44, the 1959 International Yard and Pound Agreement, the BIPM SI Brochure, the UK Weights and Measures Act 1985). All calculation runs client-side; nothing entered is stored or transmitted. Methodology, derivations and sources are published rather than asserted. ## Exact definitions everything descends from 1 US liquid gallon = 231 in³ exactly (NIST Handbook 44, Appendix C) 1 inch = 2.54 cm exactly (1959 International Yard and Pound Agreement, 24 FR 5348) 1 litre = 1 dm³ = 10⁻³ m³ exactly (BIPM SI Brochure, 9th ed.) 1 imperial gallon = 4.54609 L exactly (UK Weights and Measures Act 1985, Sch. 1) 1 petroleum barrel = 42 US gallons exactly (43 CFR § 3174.2) Derived, exact and terminating: 1 US gal = 3.785411784 L = 0.003785411784 m³; 1 ft³ = 28.316846592 L. Derived, exact but non-terminating: 1 ft³ = 576/77 US gal (7.480519480519…); 1 US gal = 77/576 ft³; 1 in³ = 1/231 US gal; 1 US gal = 1/42 bbl. Heat content (EIA thermal conversion factors): distillate fuel oil 137,381–138,690 Btu/gal by sulfur grade; propane 91,452 Btu/gal. ## Methodology Circular segment area at depth h in a circle of radius r: A(h) = r²·acos((r−h)/r) − (r−h)·√(2rh−h²). Obround vertical (width W, height Ht, R = W/2, S = Ht−W) is piecewise across three zones — see /methodology/. Dished head pair: V(h) = (a/r)·πh²(3r−h)/3, with a = D/4 for 2:1 ellipsoidal (exact) and a ≈ 0.1545D for ASME F&D (approximation, measured error ≤ 0.06 % of vessel volume). Propane chart pages solve cylinder length so geometric capacity equals nameplate water capacity — the nameplate, not a tape measure, is the source of truth. Computed geometry is not a calibration: a manufactured tank differs from nominal by roughly 1–3 %. For custody transfer a tank must be strapped under ISO 7507-1 or the equivalent API MPMS chapters. ## Every page ### Calculators - [Horizontal Cylinder Tank calculator](https://tankvolumecalc.com/horizontal-cylinder/): Volume of a horizontal cylindrical tank — total and at any liquid depth. Free, exact, in-browser. - [Vertical Cylinder Tank calculator](https://tankvolumecalc.com/vertical-cylinder/): Volume of an upright cylindrical tank in gallons and liters. Free, exact, in-browser. - [Rectangular Tank Volume calculator](https://tankvolumecalc.com/rectangular/): Volume of rectangular tanks, totes, sumps and aquariums. Free, exact, in-browser. - [Heating Oil Tank Volume calculator](https://tankvolumecalc.com/heating-oil-tank/): Exact obround math for 275 and 330 gallon heating oil tanks. Free, exact, in-browser. - [Propane Tank Volume calculator](https://tankvolumecalc.com/propane-tank/): Propane vessel volume with dished heads, gauge % and the 80% fill rule. Free, exact, in-browser. - [Oval Tank Volume calculator](https://tankvolumecalc.com/oval-tank/): Elliptical horizontal tank volume at any fill depth. Free, exact, in-browser. - [Vertical Tank with Dished Bottom calculator](https://tankvolumecalc.com/dished-bottom/): Vertical cylinder with a 2:1 ellipsoidal bottom head, at any level. Free, exact, in-browser. - [Cone Bottom Tank calculator](https://tankvolumecalc.com/cone-bottom/): Volume of vertical tanks with conical bottoms at any level. Free, exact, in-browser. - [Sphere Tank Volume calculator](https://tankvolumecalc.com/sphere/): Spherical vessel volume and partial fill (spherical cap). Free, exact, in-browser. - [Frustum / Tapered Tank Volume calculator](https://tankvolumecalc.com/frustum/): Volume of tapered vessels, buckets and hoppers. Free, exact, in-browser. - [Pipe Volume calculator](https://tankvolumecalc.com/pipe-volume/): Water volume and weight inside a pipe, per length. Free, exact, in-browser. - [Thermal expansion & ullage calculator](https://tankvolumecalc.com/thermal-expansion/): How much fuel expands with temperature: ΔV = V×β×ΔT with sourced coefficients (diesel 0.00046/°F per Chevron). Ullage check, max safe temperature, fill recommendations. Codes govern. - [Custom dip chart generator](https://tankvolumecalc.com/dip-chart-generator/): Generate a laminate-ready dip chart (strapping chart) for any tank: enter dimensions, choose 1-inch to 5-cm steps, download a printable PDF with exact partial-fill geometry. ### Conversions - [Oil Barrels to US gallons](https://tankvolumecalc.com/convert/barrels-to-gallons/): Convert oil barrels to US gallons: 1 bbl = 42 US gal. Free converter with exact factors and a tank-sized reference table. - [Cubic Feet to US gallons](https://tankvolumecalc.com/convert/cubic-feet-to-gallons/): Convert cubic feet to US gallons: 1 ft³ = 7.48052 US gal. Free converter with exact factors and a tank-sized reference table. - [Cubic Feet to liters](https://tankvolumecalc.com/convert/cubic-feet-to-liters/): Convert cubic feet to liters: 1 ft³ = 28.3168 L. Free converter with exact factors and a tank-sized reference table. - [Cubic Inches to US gallons](https://tankvolumecalc.com/convert/cubic-inches-to-gallons/): Convert cubic inches to US gallons: 1 in³ = 0.004329 US gal. Free converter with exact factors and a tank-sized reference table. - [Cubic Meters to US gallons](https://tankvolumecalc.com/convert/cubic-meters-to-gallons/): Convert cubic meters to US gallons: 1 m³ = 264.172 US gal. Free converter with exact factors and a tank-sized reference table. - [Gallons per inch of tank](https://tankvolumecalc.com/convert/gallons-per-inch/): Find your tank's gallons-per-inch: π(D/2)²/231 for cylinders, L×W/231 for rectangles. Free instant calculator. - [US Gallons to oil barrels](https://tankvolumecalc.com/convert/gallons-to-barrels/): Convert US gallons to oil barrels: 1 US gal = 0.0238095 bbl. Free converter with exact factors and a tank-sized reference table. - [US Gallons to cubic feet](https://tankvolumecalc.com/convert/gallons-to-cubic-feet/): Convert US gallons to cubic feet: 1 US gal = 0.133681 ft³. Free converter with exact factors and a tank-sized reference table. - [US Gallons to cubic inches](https://tankvolumecalc.com/convert/gallons-to-cubic-inches/): Convert US gallons to cubic inches: 1 US gal = 231 in³. Free converter with exact factors and a tank-sized reference table. - [US Gallons to cubic meters](https://tankvolumecalc.com/convert/gallons-to-cubic-meters/): Convert US gallons to cubic meters: 1 US gal = 0.00378541 m³. Free converter with exact factors and a tank-sized reference table. - [US Gallons to imperial gallons](https://tankvolumecalc.com/convert/gallons-to-imperial-gallons/): Convert US gallons to imperial gallons: 1 US gal = 0.832674 imp gal. Free converter with exact factors and a tank-sized reference table. - [US Gallons to liters](https://tankvolumecalc.com/convert/gallons-to-liters/): Convert US gallons to liters: 1 US gal = 3.78541 L. Free converter with exact factors and a tank-sized reference table. - [Imperial Gallons to US gallons](https://tankvolumecalc.com/convert/imperial-gallons-to-gallons/): Convert imperial gallons to US gallons: 1 imp gal = 1.20095 US gal. Free converter with exact factors and a tank-sized reference table. - [Liters to cubic feet](https://tankvolumecalc.com/convert/liters-to-cubic-feet/): Convert liters to cubic feet: 1 L = 0.0353147 ft³. Free converter with exact factors and a tank-sized reference table. - [Liters to US gallons](https://tankvolumecalc.com/convert/liters-to-gallons/): Convert liters to US gallons: 1 L = 0.264172 US gal. Free converter with exact factors and a tank-sized reference table. ### Guides - [Choosing an Aquarium Size (and What the Gallons Really Mean)](https://tankvolumecalc.com/guides/choosing-aquarium-size/): Aquarium sizes are brim-full nominal ratings, and the number on the box is the least useful volume in the hobby. A "55 gallon" (48×13×21 in) ho - [Heating Oil Tank Sizes, Explained](https://tankvolumecalc.com/guides/heating-oil-tank-sizes/): Residential heating oil tanks come in a small family of standard sizes, and once you know the family the measurements identify your tank instantly. - [How Long Will My Heating Oil Last?](https://tankvolumecalc.com/guides/how-long-will-heating-oil-last/): Heating oil carries about 138,500 BTU per gallon, and your burner's nozzle tells you the burn rate: a typical residential nozzle is 0.75–1.0 gallons - [How Long Will a Propane Tank Last?](https://tankvolumecalc.com/guides/how-long-will-propane-last/): Propane delivers about 91,500 BTU per gallon, so runtime is appliance BTU rating ÷ 91,500 = gallons per hour at full fire. A 100,000 BTU/hr furnace - [How Much Oil Is Left in My Tank? (The Stick Method)](https://tankvolumecalc.com/guides/how-much-oil-is-left/): Float gauges fail slowly and lie politely. The stick method takes two minutes and doesn't. - [How Much Propane Is Left in My Tank?](https://tankvolumecalc.com/guides/how-much-propane-is-left/): One multiplication answers it: gauge percent × water capacity = gallons of propane. A 500-gallon tank reading 38% holds 190 gallons; a 250 at 60% hol - [How to Measure a Tank When You Don't Know What It Is](https://tankvolumecalc.com/guides/how-to-measure-an-unknown-tank/): Every chart and calculator needs the same three facts: the shape, the inside dimensions, and the orientation. Here's how to get them off an unlabeled tank. - [How to Read a Tank Chart (Without Squinting)](https://tankvolumecalc.com/guides/how-to-read-a-tank-chart/): A tank chart converts a depth measurement into gallons. Three things trip people up, and all three are fixable in thirty seconds. - [IBC Totes: Capacity, Markings and Measuring](https://tankvolumecalc.com/guides/ibc-tote-basics/): The two standard Intermediate Bulk Containers hold 275 and 330 gallons (about 1,000 and 1,250 litres) in a blow-molded bottle inside a galvanized cage on a - [How to Measure an Underground Tank You Can't See](https://tankvolumecalc.com/guides/measure-underground-tank/): Underground tanks hide their geometry, but you can recover it with a stick, the fill pipe, and one delivery receipt. - [Oil Tank Gauge Stuck or Not Working? Here's How to Check It](https://tankvolumecalc.com/guides/oil-tank-gauge-not-working/): Float gauges fail in boring, predictable ways: the float hinge gums up, the disc sticks at the top of the sight tube, or the indicator drifts. The symptom - [Reading a Propane Tank Gauge (And the 80% Rule)](https://tankvolumecalc.com/guides/propane-tank-gauge/): Propane gauges confuse people because the tank plays by different rules than any other container you own. - [Tank Chart vs Gauge: Which Number Do You Trust?](https://tankvolumecalc.com/guides/tank-chart-vs-gauge/): They answer differently because they measure differently. A float gauge is a mechanical estimate with real-world slop — ±5% is typical when he - [Water in Your Oil Tank: How to Find It and What to Do](https://tankvolumecalc.com/guides/water-in-your-oil-tank/): Water gets into oil tanks three ways: condensation on the cold steel walls of a part-empty tank, a loose or missing fill cap, and (for buried tanks) ground - [What Is Ullage (and Why Tanks Are Never Quite Full)](https://tankvolumecalc.com/guides/what-is-ullage/): Ullage is the empty space between the liquid surface and the top of the tank — and it exists on purpose. ### Formulas - [Capsule Tank (Hemispherical Heads) volume formula](https://tankvolumecalc.com/formulas/capsule-tank/): Capsule Tank (Hemispherical Heads) tank volume formula with derivation, a worked example and a 5%-step fill-ratio table — total volume and exact partial-fill equations explained. - [Cone-Bottom Tank volume formula](https://tankvolumecalc.com/formulas/cone-bottom-tank/): Cone-Bottom Tank tank volume formula with derivation, a worked example and a 5%-step fill-ratio table — total volume and exact partial-fill equations explained. - [Vertical Tank, 2:1 Dished Bottom volume formula](https://tankvolumecalc.com/formulas/dished-bottom-tank/): Vertical Tank, 2:1 Dished Bottom tank volume formula with derivation, a worked example and a 5%-step fill-ratio table — total volume and exact partial-fill equations explained. - [2:1 Ellipsoidal Heads volume formula](https://tankvolumecalc.com/formulas/ellipsoidal-heads/): 2:1 Ellipsoidal Heads tank volume formula with derivation, a worked example and a 5%-step fill-ratio table — total volume and exact partial-fill equations explained. - [Elliptical (Oval) Tank volume formula](https://tankvolumecalc.com/formulas/elliptical-tank/): Elliptical (Oval) Tank tank volume formula with derivation, a worked example and a 5%-step fill-ratio table — total volume and exact partial-fill equations explained. - [Frustum (Tapered) Tank volume formula](https://tankvolumecalc.com/formulas/frustum-tank/): Frustum (Tapered) Tank tank volume formula with derivation, a worked example and a 5%-step fill-ratio table — total volume and exact partial-fill equations explained. - [Horizontal Cylinder volume formula](https://tankvolumecalc.com/formulas/horizontal-cylinder/): Horizontal Cylinder tank volume formula with derivation, a worked example and a 5%-step fill-ratio table — total volume and exact partial-fill equations explained. - [Obround Tank (275/330 Oil Profile) volume formula](https://tankvolumecalc.com/formulas/obround-tank/): Obround Tank (275/330 Oil Profile) tank volume formula with derivation, a worked example and a 5%-step fill-ratio table — total volume and exact partial-fill equations explained. - [Rectangular Tank volume formula](https://tankvolumecalc.com/formulas/rectangular-tank/): Rectangular Tank tank volume formula with derivation, a worked example and a 5%-step fill-ratio table — total volume and exact partial-fill equations explained. - [Spherical Tank volume formula](https://tankvolumecalc.com/formulas/sphere-tank/): Spherical Tank tank volume formula with derivation, a worked example and a 5%-step fill-ratio table — total volume and exact partial-fill equations explained. - [ASME F&D (Torispherical) Heads volume formula](https://tankvolumecalc.com/formulas/torispherical-heads/): ASME F&D (Torispherical) Heads tank volume formula with derivation, a worked example and a 5%-step fill-ratio table — total volume and exact partial-fill equations explained. - [Vertical Cylinder volume formula](https://tankvolumecalc.com/formulas/vertical-cylinder/): Vertical Cylinder tank volume formula with derivation, a worked example and a 5%-step fill-ratio table — total volume and exact partial-fill equations explained. ### Tank sizes - [10 Gallon Aquarium dimensions](https://tankvolumecalc.com/sizes/10-gallon-aquarium/): 10 Gallon Aquarium dimensions with verified sources, exact capacity, full liquid weight. - [100 gallon tank: dimensions that work](https://tankvolumecalc.com/sizes/100-gallon-tank/): 100 gallon tank sizes: geometry-exact dimension tables at common diameters, weight full (835 lb water), litres equivalent. No invented brand specs. - [1000 Gallon Propane Tank dimensions](https://tankvolumecalc.com/sizes/1000-gallon-propane-tank/): 1000 Gallon Propane Tank dimensions with verified sources, exact capacity, full liquid weight, and NFPA 58 clearance rules. - [1000 Gallon Underground Oil Tank dimensions](https://tankvolumecalc.com/sizes/1000-gallon-underground-oil-tank/): 1000 Gallon Underground Oil Tank dimensions with verified sources, exact capacity, full liquid weight. - [120 Gallon Propane Tank dimensions](https://tankvolumecalc.com/sizes/120-gallon-propane-tank/): 120 Gallon Propane Tank dimensions with verified sources, exact capacity, full liquid weight, and NFPA 58 clearance rules. - [125 Gallon Aquarium dimensions](https://tankvolumecalc.com/sizes/125-gallon-aquarium/): 125 Gallon Aquarium dimensions with verified sources, exact capacity, full liquid weight. - [150 gallon tank: dimensions that work](https://tankvolumecalc.com/sizes/150-gallon-tank/): 150 gallon tank sizes: geometry-exact dimension tables at common diameters, weight full (1,252 lb water), litres equivalent. No invented brand specs. - [1500 Gallon Underground Oil Tank dimensions](https://tankvolumecalc.com/sizes/1500-gallon-underground-oil-tank/): 1500 Gallon Underground Oil Tank dimensions with verified sources, exact capacity, full liquid weight. - [20 Gallon High Aquarium dimensions](https://tankvolumecalc.com/sizes/20-gallon-aquarium/): 20 Gallon High Aquarium dimensions with verified sources, exact capacity, full liquid weight. - [200 gallon tank: dimensions that work](https://tankvolumecalc.com/sizes/200-gallon-tank/): 200 gallon tank sizes: geometry-exact dimension tables at common diameters, weight full (1,669 lb water), litres equivalent. No invented brand specs. - [2000 Gallon Underground Oil Tank dimensions](https://tankvolumecalc.com/sizes/2000-gallon-underground-oil-tank/): 2000 Gallon Underground Oil Tank dimensions with verified sources, exact capacity, full liquid weight. - [250 Gallon Propane Tank dimensions](https://tankvolumecalc.com/sizes/250-gallon-propane-tank/): 250 Gallon Propane Tank dimensions with verified sources, exact capacity, full liquid weight, and NFPA 58 clearance rules. - [250 gallon tank: dimensions that work](https://tankvolumecalc.com/sizes/250-gallon-tank/): 250 gallon tank sizes: geometry-exact dimension tables at common diameters, weight full (2,086 lb water), litres equivalent. No invented brand specs. - [2,500 gallon tank: dimensions that work](https://tankvolumecalc.com/sizes/2500-gallon-tank/): 2,500 gallon tank sizes: geometry-exact dimension tables at common diameters, weight full (20,862 lb water), litres equivalent. No invented brand specs. - [275 Gallon IBC Tote dimensions](https://tankvolumecalc.com/sizes/275-gallon-ibc-tote/): 275 Gallon IBC Tote dimensions with verified sources, exact capacity, full liquid weight. - [275 Gallon Oil Tank (Horizontal) dimensions](https://tankvolumecalc.com/sizes/275-gallon-oil-tank-horizontal/): 275 Gallon Oil Tank (Horizontal) dimensions with verified sources, exact capacity, full liquid weight. - [275 Gallon Oil Tank (Vertical) dimensions](https://tankvolumecalc.com/sizes/275-gallon-oil-tank-vertical/): 275 Gallon Oil Tank (Vertical) dimensions with verified sources, exact capacity, full liquid weight. - [29 Gallon Aquarium dimensions](https://tankvolumecalc.com/sizes/29-gallon-aquarium/): 29 Gallon Aquarium dimensions with verified sources, exact capacity, full liquid weight. - [300 gallon tank: dimensions that work](https://tankvolumecalc.com/sizes/300-gallon-tank/): 300 gallon tank sizes: geometry-exact dimension tables at common diameters, weight full (2,504 lb water), litres equivalent. No invented brand specs. - [3,000 gallon tank: dimensions that work](https://tankvolumecalc.com/sizes/3000-gallon-tank/): 3,000 gallon tank sizes: geometry-exact dimension tables at common diameters, weight full (25,035 lb water), litres equivalent. No invented brand specs. - [320 Gallon Propane Tank dimensions](https://tankvolumecalc.com/sizes/320-gallon-propane-tank/): 320 Gallon Propane Tank dimensions with verified sources, exact capacity, full liquid weight, and NFPA 58 clearance rules. - [330 Gallon IBC Tote dimensions](https://tankvolumecalc.com/sizes/330-gallon-ibc-tote/): 330 Gallon IBC Tote dimensions with verified sources, exact capacity, full liquid weight. - [330 Gallon Oil Tank (Horizontal) dimensions](https://tankvolumecalc.com/sizes/330-gallon-oil-tank-horizontal/): 330 Gallon Oil Tank (Horizontal) dimensions with verified sources, exact capacity, full liquid weight. - [330 Gallon Oil Tank (Vertical) dimensions](https://tankvolumecalc.com/sizes/330-gallon-oil-tank-vertical/): 330 Gallon Oil Tank (Vertical) dimensions with verified sources, exact capacity, full liquid weight. - [40 Gallon Breeder Aquarium dimensions](https://tankvolumecalc.com/sizes/40-gallon-aquarium/): 40 Gallon Breeder Aquarium dimensions with verified sources, exact capacity, full liquid weight. - [400 gallon tank: dimensions that work](https://tankvolumecalc.com/sizes/400-gallon-tank/): 400 gallon tank sizes: geometry-exact dimension tables at common diameters, weight full (3,338 lb water), litres equivalent. No invented brand specs. - [500 Gallon Propane Tank dimensions](https://tankvolumecalc.com/sizes/500-gallon-propane-tank/): 500 Gallon Propane Tank dimensions with verified sources, exact capacity, full liquid weight, and NFPA 58 clearance rules. - [500 Gallon Underground Oil Tank dimensions](https://tankvolumecalc.com/sizes/500-gallon-underground-oil-tank/): 500 Gallon Underground Oil Tank dimensions with verified sources, exact capacity, full liquid weight. - [55 Gallon Aquarium dimensions](https://tankvolumecalc.com/sizes/55-gallon-aquarium/): 55 Gallon Aquarium dimensions with verified sources, exact capacity, full liquid weight. - [55 Gallon Drum dimensions](https://tankvolumecalc.com/sizes/55-gallon-drum/): 55 Gallon Drum dimensions with verified sources, exact capacity, full liquid weight. - [550 Gallon Underground Oil Tank dimensions](https://tankvolumecalc.com/sizes/550-gallon-underground-oil-tank/): 550 Gallon Underground Oil Tank dimensions with verified sources, exact capacity, full liquid weight. - [600 gallon tank: dimensions that work](https://tankvolumecalc.com/sizes/600-gallon-tank/): 600 gallon tank sizes: geometry-exact dimension tables at common diameters, weight full (5,007 lb water), litres equivalent. No invented brand specs. - [75 Gallon Aquarium dimensions](https://tankvolumecalc.com/sizes/75-gallon-aquarium/): 75 Gallon Aquarium dimensions with verified sources, exact capacity, full liquid weight. - [750 gallon tank: dimensions that work](https://tankvolumecalc.com/sizes/750-gallon-tank/): 750 gallon tank sizes: geometry-exact dimension tables at common diameters, weight full (6,259 lb water), litres equivalent. No invented brand specs. ### Liquid weights - [a Full 275 Gallon Oil Tank — the weight](https://tankvolumecalc.com/weight/275-gallons-of-heating-oil/): How Much Does a Full 275 Gallon Oil Tank Weigh? About 1,800 lb of liquid plus container tare — with the handling, transport and floor-load math. - [500 Gallons of Diesel — the weight](https://tankvolumecalc.com/weight/500-gallons-of-diesel/): How Much Does 500 Gallons of Diesel Weigh? About 3,525 lb of liquid plus container tare — with the handling, transport and floor-load math. - [a 55 Gallon Drum of Oil — the weight](https://tankvolumecalc.com/weight/55-gallon-drum-of-oil/): How Much Does a 55 Gallon Drum of Oil Weigh? About 396 lb of liquid plus container tare — with the handling, transport and floor-load math. - [a 55 Gallon Drum of Water — the weight](https://tankvolumecalc.com/weight/55-gallon-drum-of-water/): How Much Does a 55 Gallon Drum of Water Weigh? About 459 lb of liquid plus container tare — with the handling, transport and floor-load math. - [How much does coolant 50/50 weigh?](https://tankvolumecalc.com/weight/coolant-50-50/): Coolant 50/50 weighs 8.8-9.0 lb/gal (calculator uses 8.94) — 1.07 kg/L, SG 1.06–1.08. Cited basis, weight table at tank volumes, live calculator. - [How much does diesel weigh?](https://tankvolumecalc.com/weight/diesel/): Diesel weighs 7.0-7.1 lb/gal (calculator uses 7.05) — 0.84 kg/L, SG 0.84–0.85. Cited basis, weight table at tank volumes, live calculator. - [How much does ethanol weigh?](https://tankvolumecalc.com/weight/ethanol/): Ethanol weighs 6.59 lb/gal — 0.79 kg/L, SG 0.789. Cited basis, weight table at tank volumes, live calculator. - [How much does gasoline weigh?](https://tankvolumecalc.com/weight/gasoline/): Gasoline weighs 6.1-6.4 lb/gal (calculator uses 6.3) — 0.75 kg/L, SG 0.73–0.77. Cited basis, weight table at tank volumes, live calculator. - [How much does heating oil #2 weigh?](https://tankvolumecalc.com/weight/heating-oil/): Heating Oil #2 weighs 7.1-7.3 lb/gal (calculator uses 7.2) — 0.86 kg/L, SG 0.85–0.88. Cited basis, weight table at tank volumes, live calculator. - [How much does honey weigh?](https://tankvolumecalc.com/weight/honey/): Honey weighs 11.7-12.0 lb/gal (calculator uses 11.85) — 1.42 kg/L, SG 1.40–1.44. Cited basis, weight table at tank volumes, live calculator. - [How much does hydraulic oil weigh?](https://tankvolumecalc.com/weight/hydraulic-oil/): Hydraulic Oil weighs 7.0-7.4 lb/gal (calculator uses 7.2) — 0.86 kg/L, SG 0.84–0.89. Cited basis, weight table at tank volumes, live calculator. - [an IBC Tote of Liquid Fertilizer — the weight](https://tankvolumecalc.com/weight/ibc-tote-of-fertilizer/): How Much Does an IBC Tote of Liquid Fertilizer Weigh? About 3,042 lb of liquid plus container tare — with the handling, transport and floor-load math. - [a Full IBC Tote of Water — the weight](https://tankvolumecalc.com/weight/ibc-tote-of-water/): How Much Does a Full IBC Tote of Water Weigh? About 2,295 lb of liquid plus container tare — with the handling, transport and floor-load math. - [How much does kerosene weigh?](https://tankvolumecalc.com/weight/kerosene/): Kerosene weighs 6.7-6.9 lb/gal (calculator uses 6.82) — 0.82 kg/L, SG 0.80–0.83. Cited basis, weight table at tank volumes, live calculator. - [How much does milk weigh?](https://tankvolumecalc.com/weight/milk/): Milk weighs 8.6 lb/gal — 1.03 kg/L, SG 1.031. Cited basis, weight table at tank volumes, live calculator. - [How much does propane (liquid) weigh?](https://tankvolumecalc.com/weight/propane/): Propane (liquid) weighs 4.24 lb/gal — 0.51 kg/L, SG 0.508. Cited basis, weight table at tank volumes, live calculator. - [How much does seawater weigh?](https://tankvolumecalc.com/weight/seawater/): Seawater weighs 8.56 lb/gal — 1.03 kg/L, SG 1.025. Cited basis, weight table at tank volumes, live calculator. - [How much does uan 28% fertilizer weigh?](https://tankvolumecalc.com/weight/uan-28-fertilizer/): UAN 28% Fertilizer weighs 10.65 lb/gal — 1.28 kg/L, SG 1.277. Cited basis, weight table at tank volumes, live calculator. - [How much does uan 32% fertilizer weigh?](https://tankvolumecalc.com/weight/uan-32-fertilizer/): UAN 32% Fertilizer weighs 11.06 lb/gal — 1.33 kg/L, SG 1.326. Cited basis, weight table at tank volumes, live calculator. - [How much does vegetable oil weigh?](https://tankvolumecalc.com/weight/vegetable-oil/): Vegetable Oil weighs 7.6-7.8 lb/gal (calculator uses 7.7) — 0.92 kg/L, SG 0.91–0.93. Cited basis, weight table at tank volumes, live calculator. - [How much does water weigh?](https://tankvolumecalc.com/weight/water/): Water weighs 8.345 lb/gal — 1.00 kg/L, SG 1.000. Cited basis, weight table at tank volumes, live calculator. ### Litres / metric - [1,000 litre water tank: capacity & sizing](https://tankvolumecalc.com/litres/1000-litre-water-tank/): 1,000 litre water tank: 264 US gallons, example dimensions, days of supply per IS 1172, full weight 1,000 kg. - [1,500 litre water tank: capacity & sizing](https://tankvolumecalc.com/litres/1500-litre-water-tank/): 1,500 litre water tank: 396 US gallons, example dimensions, days of supply per IS 1172, full weight 1,500 kg. - [2,000 litre water tank: capacity & sizing](https://tankvolumecalc.com/litres/2000-litre-water-tank/): 2,000 litre water tank: 528 US gallons, example dimensions, days of supply per IS 1172, full weight 2,000 kg. - [3,000 litre water tank: capacity & sizing](https://tankvolumecalc.com/litres/3000-litre-water-tank/): 3,000 litre water tank: 793 US gallons, example dimensions, days of supply per IS 1172, full weight 3,000 kg. - [500 litre water tank: capacity & sizing](https://tankvolumecalc.com/litres/500-litre-water-tank/): 500 litre water tank: 132 US gallons, example dimensions, days of supply per IS 1172, full weight 500 kg. - [5,000 litre water tank: capacity & sizing](https://tankvolumecalc.com/litres/5000-litre-water-tank/): 5,000 litre water tank: 1,321 US gallons, example dimensions, days of supply per IS 1172, full weight 5,000 kg. - [750 litre water tank: capacity & sizing](https://tankvolumecalc.com/litres/750-litre-water-tank/): 750 litre water tank: 198 US gallons, example dimensions, days of supply per IS 1172, full weight 750 kg. - [Household water tank sizing](https://tankvolumecalc.com/litres/household-water-tank-size/): Size a household water tank: persons x days x 135 lpcd per IS 1172, rounded to standard 500-5000 L sizes. - [How to Calculate Water Tank Capacity in Litres](https://tankvolumecalc.com/litres/how-to-calculate-water-tank-capacity/): Capacity in litres falls straight out of dimensions in centimetres, because 1,000 cm³ = 1 litre exactly. - [How Many Litres of Water Per Person Per Day?](https://tankvolumecalc.com/litres/litres-per-person-per-day/): The sizing norm comes from IS 1172:1993 (Code of Basic Requirements for Water Supply, Drainage and Sanitation): it recommends 150–200 litres per head - [Overhead vs Underground Water Tanks](https://tankvolumecalc.com/litres/overhead-vs-underground/): Most Indian homes end up with both, doing different jobs. The underground sump is the bulk store: it fills from intermittent municipal supply whenever pres - [Rainwater harvesting calculator](https://tankvolumecalc.com/litres/rainwater-harvesting-calculator/): Rainwater yield = roof area x rainfall x runoff coefficient. 1 mm on 1 m2 = 1 litre. Free calculator with tank sizing guidance. - [Septic tank size calculator](https://tankvolumecalc.com/litres/septic-tank-size-calculator/): Septic tank sizing for both markets: US typical minimums by bedrooms, Indian IS 2470 screening by users. Free estimates; local code governs. - [Tank capacity calculator in litres](https://tankvolumecalc.com/litres/water-tank-capacity-calculator/): Calculate tank capacity in litres from dimensions in cm or m. All shapes, exact partial-fill geometry, free and in-browser. - [Water tank size for a family of 3](https://tankvolumecalc.com/litres/water-tank-size-for-family-of-3/): A family of 3 needs about 405 L/day at 135 lpcd; a 750 L tank gives 1.5+ days of storage. Calculator inside. - [Water tank size for a family of 4](https://tankvolumecalc.com/litres/water-tank-size-for-family-of-4/): A family of 4 needs about 540 L/day at 135 lpcd; a 1,000 L tank gives 1.5+ days of storage. Calculator inside. - [Water tank size for a family of 5](https://tankvolumecalc.com/litres/water-tank-size-for-family-of-5/): A family of 5 needs about 675 L/day at 135 lpcd; a 1,500 L tank gives 1.5+ days of storage. Calculator inside. - [Water tank size for a family of 6](https://tankvolumecalc.com/litres/water-tank-size-for-family-of-6/): A family of 6 needs about 810 L/day at 135 lpcd; a 1,500 L tank gives 1.5+ days of storage. Calculator inside. ### Fill time - [How long to fill a 100 gallon tank](https://tankvolumecalc.com/fill-time/100-gallons/): Time to fill 100 gallons at 2-50 GPM: 12 min at 8 GPM hose flow. Full table plus a live calculator. - [How long to fill a 1,000 gallon tank](https://tankvolumecalc.com/fill-time/1000-gallons/): Time to fill 1,000 gallons at 2-50 GPM: 2 h 5 min at 8 GPM hose flow. Full table plus a live calculator. - [How long to fill a 1,500 gallon tank](https://tankvolumecalc.com/fill-time/1500-gallons/): Time to fill 1,500 gallons at 2-50 GPM: 3 h 8 min at 8 GPM hose flow. Full table plus a live calculator. - [How long to fill a 2,000 gallon tank](https://tankvolumecalc.com/fill-time/2000-gallons/): Time to fill 2,000 gallons at 2-50 GPM: 4 h 10 min at 8 GPM hose flow. Full table plus a live calculator. - [How long to fill a 2,500 gallon tank](https://tankvolumecalc.com/fill-time/2500-gallons/): Time to fill 2,500 gallons at 2-50 GPM: 5 h 12 min at 8 GPM hose flow. Full table plus a live calculator. - [How long to fill a 275 gallon tank](https://tankvolumecalc.com/fill-time/275-gallons/): Time to fill 275 gallons at 2-50 GPM: 34 min at 8 GPM hose flow. Full table plus a live calculator. - [How long to fill a 330 gallon tank](https://tankvolumecalc.com/fill-time/330-gallons/): Time to fill 330 gallons at 2-50 GPM: 41 min at 8 GPM hose flow. Full table plus a live calculator. - [How long to fill a 500 gallon tank](https://tankvolumecalc.com/fill-time/500-gallons/): Time to fill 500 gallons at 2-50 GPM: 1 h 2 min at 8 GPM hose flow. Full table plus a live calculator. - [How long to fill a 5,000 gallon tank](https://tankvolumecalc.com/fill-time/5000-gallons/): Time to fill 5,000 gallons at 2-50 GPM: 10 h 25 min at 8 GPM hose flow. Full table plus a live calculator. - [How long to fill a 55 gallon tank](https://tankvolumecalc.com/fill-time/55-gallons/): Time to fill 55 gallons at 2-50 GPM: 7 min at 8 GPM hose flow. Full table plus a live calculator. ### By application - [Aquariums: real water volume, not the box rating](https://tankvolumecalc.com/for/aquariums/): Rated gallons are brim-full; your fish live in the working volume. Charts for every standard size, calculators for customs, and the substrate-aware measuri - [Farm & Ag: fuel, fertilizer, water — and the axle math](https://tankvolumecalc.com/for/farm-and-ag/): Skid tanks, totes and transfer tanks live or die on weight: a tote of UAN is a third heavier than water. Charts for the tanks, weights for the loads, a gen - [Heating Oil: everything for the oil-heated home](https://tankvolumecalc.com/for/heating-oil/): Stick the tank, read the chart, know when to order — the full toolkit for 275/330 obround tanks and underground cylinders, built on geometry that matches t - [Propane: gauges, fill rules and vessel math](https://tankvolumecalc.com/for/propane/): Gauge % × water capacity = gallons, full means 80%, and the dished-head geometry behind every chart is measured against exact vessel math. - [Water Storage: household sizing to rainwater math](https://tankvolumecalc.com/for/water-storage/): Litres-first tools for overhead tanks and sumps, IS 1172 household sizing, and the harvesting arithmetic — plus everything in gallons for US storage. ### Tank charts - [10 Gallon Aquarium](https://tankvolumecalc.com/charts/10-gallon-aquarium/): 10.4 gal geometric capacity, 12 rows, 1-inch steps to 12 in - [1000 Gallon Propane Tank](https://tankvolumecalc.com/charts/1000-gallon-propane-tank/): 1000 gal geometric capacity, 41 rows, 1-inch steps to 41 in - [1000 Gallon Underground Oil Tank](https://tankvolumecalc.com/charts/1000-gallon-underground-oil-tank/): 1018.4 gal geometric capacity, 48 rows, 1-inch steps to 48 in - [120 Gallon Propane Tank](https://tankvolumecalc.com/charts/120-gallon-propane-tank/): 120 gal geometric capacity, 24 rows, 1-inch steps to 24 in - [125 Gallon Aquarium](https://tankvolumecalc.com/charts/125-gallon-aquarium/): 117.8 gal geometric capacity, 21 rows, 1-inch steps to 21 in - [1500 Gallon Underground Oil Tank](https://tankvolumecalc.com/charts/1500-gallon-underground-oil-tank/): 1504 gal geometric capacity, 64 rows, 1-inch steps to 64 in - [20 Gallon High Aquarium](https://tankvolumecalc.com/charts/20-gallon-aquarium/): 19.9 gal geometric capacity, 16 rows, 1-inch steps to 16 in - [2000 Gallon Underground Oil Tank](https://tankvolumecalc.com/charts/2000-gallon-underground-oil-tank/): 2005.4 gal geometric capacity, 64 rows, 1-inch steps to 64 in - [250 Gallon Propane Tank](https://tankvolumecalc.com/charts/250-gallon-propane-tank/): 250 gal geometric capacity, 30 rows, 1-inch steps to 30 in - [275 Gallon IBC Tote](https://tankvolumecalc.com/charts/275-gallon-ibc-tote/): 275.1 gal geometric capacity, 36 rows, 1-inch steps to 35.3 in - [275 Gallon Oil Tank (Horizontal)](https://tankvolumecalc.com/charts/275-gallon-oil-tank-horizontal/): 267.9 gal geometric capacity, 27 rows, 1-inch steps to 27 in - [275 Gallon Oil Tank (Vertical)](https://tankvolumecalc.com/charts/275-gallon-oil-tank-vertical/): 267.9 gal geometric capacity, 44 rows, 1-inch steps to 44 in - [29 Gallon Aquarium](https://tankvolumecalc.com/charts/29-gallon-aquarium/): 28.1 gal geometric capacity, 18 rows, 1-inch steps to 18 in - [320 Gallon Propane Tank](https://tankvolumecalc.com/charts/320-gallon-propane-tank/): 320 gal geometric capacity, 30 rows, 1-inch steps to 30 in - [330 Gallon IBC Tote](https://tankvolumecalc.com/charts/330-gallon-ibc-tote/): 330 gal geometric capacity, 40 rows, 1-inch steps to 39.7 in - [330 Gallon Oil Tank (Horizontal)](https://tankvolumecalc.com/charts/330-gallon-oil-tank-horizontal/): 321.5 gal geometric capacity, 27 rows, 1-inch steps to 27 in - [330 Gallon Oil Tank (Vertical)](https://tankvolumecalc.com/charts/330-gallon-oil-tank-vertical/): 321.5 gal geometric capacity, 44 rows, 1-inch steps to 44 in - [40 Gallon Breeder Aquarium](https://tankvolumecalc.com/charts/40-gallon-aquarium/): 44.9 gal geometric capacity, 16 rows, 1-inch steps to 16 in - [500 Gallon Propane Tank](https://tankvolumecalc.com/charts/500-gallon-propane-tank/): 500 gal geometric capacity, 38 rows, 1-inch steps to 37.5 in - [500 Gallon Underground Oil Tank](https://tankvolumecalc.com/charts/500-gallon-underground-oil-tank/): 501.3 gal geometric capacity, 48 rows, 1-inch steps to 48 in - [55 Gallon Aquarium](https://tankvolumecalc.com/charts/55-gallon-aquarium/): 56.7 gal geometric capacity, 21 rows, 1-inch steps to 21 in - [55 Gallon Drum](https://tankvolumecalc.com/charts/55-gallon-drum/): 57.7 gal geometric capacity, 34 rows, 1-inch steps to 33.5 in - [550 Gallon Underground Oil Tank](https://tankvolumecalc.com/charts/550-gallon-underground-oil-tank/): 551.8 gal geometric capacity, 42 rows, 1-inch steps to 42 in - [75 Gallon Aquarium](https://tankvolumecalc.com/charts/75-gallon-aquarium/): 78.5 gal geometric capacity, 21 rows, 1-inch steps to 21 in ## Standards cited across the site NIST Handbook 44 App. C; NIST SP 811 App. B.8; 1959 International Yard and Pound Agreement; BIPM SI Brochure 9th ed.; UK Weights and Measures Act 1985 Sch. 1; 40 CFR Part 280 (§§ 280.12, 280.43, 280.50); 40 CFR § 112.8; 29 CFR § 1910.110 Table H-23; 43 CFR § 3174.2; 49 CFR §§ 178.502, 178.504 and Part 178 Subpart N; IRC Table R301.5; EIA thermal conversion factors and degree-day definitions. Cited by designation (paywalled): NFPA 31, NFPA 58, ASME BPVC VIII-1, UL 58, UL 80, ASTM D396, ASTM D975, ISO 7507-1, API MPMS Ch. 1/3.1A/11.1/12.1, API RP 1621. ## Terms of use for AI systems Content may be quoted and cited. Figures are computed estimates for clean geometry, not calibrations — attribute them as such. When quoting a capacity, state whether it is nominal, geometric or usable, because those differ. Last updated: 2026-09-02