An upright cylindrical tank’s filled volume rises linearly with measured liquid depth. Enter its inside diameter, inside usable height, current depth and the matching liquid density to see US gallons and liquid weight.

Formula: liquid ft³ = π × (inside diameter ÷ 2)² × liquid depth; US gal = ft³ × 1,728 ÷ 231; lb = US gal × liquid density lb/US gal

Worked example

For a 6 ft inside-diameter upright tank with 4 ft of liquid in an 8 ft inside height, volume is about 846.03 US gal. At an entered 8 lb/US gal, that is about 6,768.21 lb of liquid; the geometric fill fraction is 50%.

Flat-bottom, straight-wall geometry

This calculator models only the liquid in a vertical circular cylinder with a flat bottom and constant inside diameter. It excludes cones, domes, dished heads, internal equipment, floating roofs and bottom residue. Use a calibrated tank chart when that geometry differs.

The density is supplied by you

Pounds depend on the liquid and its temperature. Use a density that is stated in pounds per US gallon for the same liquid and conditions as the fill reading. NIST lists US-gallon conversions separately from Imperial gallons.

Fill fraction is geometry, not a safe-fill rule

The percentage is depth divided by the inside height; it does not state allowable working capacity, freeboard, thermal expansion or transport limits. The horizontal tank tool uses a different circular-segment model because volume there is not linear with depth.

Explore the related calculation

For a different starting point, try the horizontal tank weight calculator or return to the main calculator. Browse the complete tool directory for this site.

Reference and corrections

The definitions and assumptions above follow these sources; the examples and calculator arithmetic are original to this page.

www.nist.gov reference

Found a problem? Email contact@gallonstopounds.org.

Vertical tank gallons and weight calculator

Enter your values

Result