Tank Level Calculator

Measure fill levels for cylindrical and rectangular tanks. Review volume, percentage, and usable capacity instantly. Plot level curves, export reports, and compare operating ranges.

Tank Inputs

Use height mode when you know the measured liquid depth. Use percentage mode when you know the percentage of total tank height or diameter.

Example Data Table

Tank Shape Dimensions Liquid Level Stored Volume Volume Fill
Vertical Cylinder Diameter 2.4 m, Height 5.0 m 3.1 m 14.024 m³ 62.00%
Horizontal Cylinder Diameter 2.0 m, Length 6.0 m 1.2 m 11.809 m³ 62.65%
Rectangular Tank Length 4.0 m, Width 2.5 m, Height 3.0 m 1.8 m 18.000 m³ 60.00%

Formula Used

1) Vertical Cylindrical Tank

Stored Volume: V = πr²h

Here, r is the tank radius and h is the liquid level.

2) Horizontal Cylindrical Tank

Segment Area: A = r² cos⁻¹((r − h)/r) − (r − h) √(2rh − h²)

Stored Volume: V = A × L

Here, r is radius, h is liquid level, and L is shell length.

3) Rectangular Tank

Stored Volume: V = L × W × h

Here, L is length, W is width, and h is liquid level.

4) Additional Engineering Outputs

Fill by Height: (liquid level ÷ total height) × 100

Fill by Volume: (stored volume ÷ total capacity) × 100

Headspace: total capacity − stored volume

Bottom Pressure: P = ρgh

How to Use This Calculator

  1. Choose the tank shape that matches your vessel geometry.
  2. Select a consistent length unit for every dimensional input.
  3. Enter the tank dimensions shown for your chosen shape.
  4. Pick whether your known reading is a liquid height or a height percentage.
  5. Add fluid density when you want mass and bottom pressure estimates.
  6. Set a safe fill limit to compare the current storage level against your operating target.
  7. Press the calculate button to show results above the form.
  8. Use the CSV or PDF buttons to save the generated engineering summary.

FAQs

1) What tank shapes does this calculator support?

It supports vertical cylindrical tanks, horizontal cylindrical tanks, and rectangular tanks. These shapes cover many storage, process, utility, and water system applications used in engineering and operations.

2) Why can fill by height differ from fill by volume?

In horizontal cylinders, the relationship is nonlinear. A small level change near the center can add more volume than the same level change near the bottom or top.

3) Which unit system should I use?

Use one consistent length unit for every dimension in the form. The calculator converts those values internally, then reports volume in your selected output unit.

4) Can this estimate liquid mass?

Yes. Enter the fluid density in kilograms per cubic meter. The calculator multiplies stored volume by density to estimate fluid mass inside the tank.

5) What is headspace volume?

Headspace is the empty internal volume above the liquid. It helps operators reserve expansion space, maintain safety margins, and plan refill timing more accurately.

6) What safe fill limit should I choose?

Your limit depends on the process, thermal expansion, mixing, sloshing, and operating policy. Many applications keep some freeboard instead of filling to full capacity.

7) Why does the calculator show bottom pressure?

Bottom pressure gives a quick hydrostatic estimate at the tank floor. It can help with instrument checks, level transmitter comparisons, and rough operating assessments.

8) Can I export the final results?

Yes. Use the CSV button for spreadsheet-friendly data or the PDF button for a shareable engineering summary. Both exports reflect the current calculated result set.

Related Calculators

Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.