Tank Volume Calculator
Model tank capacity from internal dimensions, then optionally calculate liquid volume at a measured fill depth. Horizontal cylinders use circular-segment geometry instead of a simple depth percentage.
How to use this calculator
Enter tank shape, required internal dimensions in feet, and current liquid depth in feet.
Review internal versus nominal dimensions, wall thickness, end-cap shape, dead volume, tilt, and manufacturer capacity.
Read full capacity, current liquid volume, fill percentage, and full capacity in liters.
Formula
Rectangular capacity = length × width × height. Vertical cylinder = πr²h. A horizontal cylinder filled to depth d uses segment area r² arccos((r − d) ÷ r) − (r − d)√(2rd − d²), multiplied by tank length.
Worked example
A 4 ft diameter vertical cylinder with a 6 ft height has capacity π × 2² × 6 = 75.398 ft³ before conversion to gallons.
Assumptions and limits
- The tank is level and matches the selected ideal geometry; fittings, rounded corners, dished heads, and inaccessible volume are excluded.
- Tank Volume Calculator treats the entered values as estimates and does not infer missing project, account, or personal details.
- Calculations retain working precision except where the cited method requires an intermediate rounding step; displayed values are then formatted separately. Source rules and dated rates must be rechecked when they change.
Sources
- National Institute of Standards and Technology: SI Units — LengthLength, area, volume, and unit-conversion conventions. Reviewed 2026-08-14.
- OpenStax: College Algebra 2eAlgebraic, ratio, radical, equation, and function formulas. Reviewed 2026-08-14.
- National Institute of Standards and Technology: Circumference, Area and VolumeOfficial formula or method source used by this calculator. Reviewed 2026-08-14.
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Verification
How this calculator is checked
Trust comes from reproducible evidence, not model confidence. You can inspect the formula, assumptions, worked example, and cited sources on this page.
- Versioned calculationFormula logic is kept separate from the interface and covered by automated registry and behavior checks.
- Cited evidenceSources linked for independent checking: 3.
- Transparent AI useAI may assist drafting or adversarial review. Agreement between models is not proof, and no human expert review is claimed unless a named reviewer is shown.
Frequently asked questions
How does the Tank Volume Calculator work?
Rectangular capacity = length × width × height. Vertical cylinder = πr²h. A horizontal cylinder filled to depth d uses segment area r² arccos((r − d) ÷ r) − (r − d)√(2rd − d²), multiplied by tank length.
What information should I enter in the Tank Volume Calculator?
Enter tank shape, required internal dimensions in feet, and current liquid depth in feet, then verify internal versus nominal dimensions, wall thickness, end-cap shape, dead volume, tilt, and manufacturer capacity.
What should I verify before using this Tank Volume Calculator result?
The tank is level and matches the selected ideal geometry; fittings, rounded corners, dished heads, and inaccessible volume are excluded.
Last updated 2026-08-25 · 1.0.0 · content-2026-08-14 · Published by YunFanLabs