Oval Cistern Capacity Calculator Elliptical Tank Capacity

Calculate elliptical tank capacity in gallons, liters, cubic feet, and cubic meters

Tank Dimensions

How to Use This Oval Tank Volume Calculator

This calculator helps you determine the exact capacity of any oval (elliptical) tank. Simply follow these steps:

  • Step 1: Enter the length (major axis), width (minor axis), and height of your tank.
  • Step 2: Select your measurement unit (Feet, Meters, Centimeters, or Inches).
  • Step 3: Choose tank orientation (horizontal or vertical).
  • Step 4: Optionally set the fill level percentage to calculate partial volume.
  • Step 5: Click "Calculate Tank Volume" to see results in multiple units.

Why Accurate Oval Tank Volume Matters

I've worked on countless projects where underestimating oval tank capacity caused major problems - from running out of water during dry spells to installing tanks that didn't fit in the designated space. That's exactly why I built this oval tank volume calculator - to help homeowners, farmers, and engineers get their elliptical tank calculations right the first time.

Whether you're planning a water storage system for a narrow basement, sizing a fuel tank for a boat, or designing an aquaculture tank, knowing your exact oval tank capacity in US Gallons, Liters, or Cubic Feet changes everything.

Oval Tank Volume Formula

The volume of an oval (elliptical) tank is calculated using the formula:

V = π × a × b × h

Where:

  • V = Volume of the tank
  • π = Pi (approximately 3.14159)
  • a = Half the length (L/2) - semi-major axis
  • b = Half the width (W/2) - semi-minor axis
  • h = Height of the tank
FromToMultiply By
Cubic Feet (ft³)US Gallons7.48052
Cubic Feet (ft³)Liters28.3168
Cubic Meters (m³)US Gallons264.172
Cubic Meters (m³)Liters1000

Pro Tips for Oval Tank Sizing

Add 20% buffer: Always oversize water storage by 20% for dry periods.
Measure inside dimensions: Tank walls take up space - measure inside.
Account for dead space: Sediment buildup reduces usable capacity.
Check local codes: Some areas require minimum water storage.
IMPORTANT DISCLAIMER: This calculator provides theoretical volume estimates. Actual tank capacity may vary due to manufacturing tolerances, temperature expansion, and sediment accumulation. Always consult tank specifications and local regulations.
- Calculate with confidence from the MultiTooSite team

Frequently Asked Questions

How do you calculate the volume of an oval tank?
Volume = π × (L/2) × (W/2) × H, where L is length, W is width, and H is height.
What is the difference between an oval tank and a cylindrical tank?
An oval tank has an elliptical cross-section (two different radii), while a cylindrical tank has a circular cross-section (one radius).
How many gallons does my oval tank hold?
Multiply cubic feet by 7.48052 to get US gallons. For metric: cubic meters × 264.172 = gallons.
What's the difference between horizontal and vertical orientation?
For horizontal oval tanks, the height dimension becomes the length of the tank. The volume formula remains the same.
Nasir Badar
Nasir Badar: Founder & Construction Estimation Expert
With 10+ years in excavation, concrete, and site work, Nasir helps contractors and homeowners create accurate real-world estimates.