Tank Level Calculator

Tank Inputs

Tank shape

Input units

Output volume unit

Diameter (optional if radius provided)

Radius (optional if diameter provided)

Measured liquid level (height from bottom)

Cylinder length (horizontal only)

Tank length (rectangular only)

Tank width (rectangular only)

Tank height (vertical/rectangular)

For spheres/horizontal cylinders, height is implied by diameter.

Fluid density (kg/m³)

Water ≈ 1000, diesel ≈ 830, gasoline ≈ 740.

Example Data Table

These examples show typical inputs and outputs for common tanks.

Tank type	Dimensions	Level	Volume (Liters)	Fill %
Vertical cylinder	r=0.50 m, H=2.00 m	h=1.20 m	942.48 L	60.00%
Horizontal cylinder	r=0.60 m, L=3.00 m	h=0.70 m	1,518.90 L	44.72%
Rectangular	L=2.00 m, W=1.20 m, H=1.50 m	h=0.90 m	2,160.00 L	60.00%
Spherical	R=0.75 m	h=0.80 m	1,168.85 L	66.09%
Vertical cylinder	d=1.00 m, H=1.20 m	h=0.30 m	235.62 L	25.00%

Formulas Used

Rectangular tank: V = L × W × h
Vertical cylinder: V = π r² h
Horizontal cylinder (partial): A = r² arccos((r − h)/r) − (r − h) √(2rh − h²), then V = A × length
Sphere (partial, spherical cap): V = π h² (3R − h) / 3
Mass and weight: m = ρV, W = m g with g = 9.80665 m/s²

All calculations are performed in meters and cubic meters internally, then converted to your selected output unit.

How to Use

Select the tank shape that matches your container.
Choose the same unit system used by your measurements.
Enter dimensions and the measured liquid level from the bottom.
Optionally set fluid density to estimate mass and weight.
Press Calculate to display volume and fill percentage.
Use the CSV/PDF buttons to export your latest result.

FAQs

1) What does “measured liquid level” mean?

It is the vertical height of liquid from the tank’s lowest internal point. For horizontal cylinders and spheres, measure from the bottom along the vertical axis.

2) Why is my level “clamped” to a maximum?

If you enter a level above the physical limit (tank height, or full diameter), the calculator limits it to the maximum so the volume never exceeds capacity.

3) Can I use diameter instead of radius?

Yes. Enter either radius or diameter. If both are entered, the radius field takes priority. Values must represent internal liquid dimensions.

4) How accurate is the horizontal cylinder formula?

It uses the circular segment method, which is standard for partially filled cylinders. Accuracy depends on correct internal radius, length, and a true vertical level measurement.

5) Does the calculator handle domed ends or rounded corners?

No. It assumes ideal shapes. For tanks with heads or complex geometry, compute the main body here and add end-cap volumes separately using manufacturer data.

6) What density should I use for fuel oils?

Use the density at your operating temperature. Typical values: diesel around 830 kg/m³ and gasoline around 740 kg/m³, but always verify with your datasheet.

7) What do the CSV and PDF exports include?

They export the latest calculation: shape, units, level used, capacity, volume, fill percentage, remaining capacity, density, mass, and weight for quick reporting.