Vertical Cylinder Tank calculator
Volume of an upright cylindrical tank in gallons and liters. Exact geometry, instant results, nothing leaves your browser.
Exact segment geometry — see methodology. Dished-head propane math is documented there too.
Upright cylinders — water storage tanks, chemical day tanks, drums — are the easy case: every inch of depth holds the same volume, so gallons scale linearly with your stick reading. The useful number this page adds is gallons per inch (capacity ÷ height), which lets you convert any gauge reading instantly.
Enter inside diameter and height. The result panel shows total capacity, the volume at your fill depth, and liquid weight — useful when checking whether a stand or floor can carry a full tank.
How this is calculated
V = πr²HV(h) = πr²hEvery slice is the same circle, so volume is exactly linear in depth. See the full derivation, a worked example and a fill-ratio table on the vertical cylinder formula page.
FAQ
TVC-102/FAQWhat is the gallons-per-inch of my tank?
Divide total gallons by height in inches — or just move the fill slider one inch and watch the filled volume change.
Does this work for a 55-gallon drum?
Yes — a standard drum is about 22.5 in inside diameter × 33.5 in, which is ~57.7 gal brim-full. See the drum chart.