Tank Volume Calculator
Calculate the total capacity and current fill volume of a cylindrical or rectangular storage tank.
Inputs explained
- Tank Shape — Choose cylindrical (vertical) or rectangular.
- Diameter / Length & Width (ft) — The tank's cross-section dimensions, depending on shape.
- Height (ft) — The tank's height.
- Fill Level (%) — How full the tank currently is, as a percentage.
How to use it
- Fill in the fields above — each input has a hint describing exactly what to enter
- Press Calculate to get your result instantly, right on this page
- Copy the result, save the tool to favorites, or share and embed it anywhere
Understanding the result
Example: A cylindrical tank 4 ft in diameter and 6 ft tall holds about 564 gallons at 100% full.
Frequently asked questions
How does the calculator handle a rectangular tank differently from a cylindrical one? For a cylindrical tank it uses the circular cross-section (radius from diameter) times height, while a rectangular tank uses length × width × height directly — selecting the wrong shape will give a significantly wrong capacity.
Does fill level assume the tank is standing upright? Yes — the percentage fill calculation assumes a vertical orientation where liquid rises evenly with height; a horizontal cylindrical tank fills non-linearly (the volume-to-height relationship isn't proportional), so this tool isn't suited to that orientation.
Is the Tank Volume Calculator free to use? Yes — it is completely free, with no sign-up, no download and no usage limits. You can use it as often as you need.
Is my data private? Yes. The calculation runs entirely in your browser — the values you enter are never sent to our servers, stored or shared with anyone.
What information do I need? Just the following: Tank Shape, Diameter / Length & Width (ft), Height (ft), Fill Level (%). Each field includes a hint explaining exactly what to enter.
Can I use it on my phone? Yes — the tool is fully responsive and works on any device, and the same calculator is available in the EasyWorkCalcs mobile app.
Privacy
Everything you enter into the Tank Volume Calculator is processed entirely in your browser. Nothing is uploaded, stored or shared — your data stays on your device.