Pool Checker
Pool Volume Calculator: Find Your Gallons & Liters | Pool Checker
Free Tool

The Smart Pool Volume Calculator

Knowing your exact pool capacity is the foundation of pool chemistry. Enter your dimensions below to get your exact volume in gallons or liters.

How to Use This Calculator

Guessing your pool's capacity is the number one reason homeowners struggle with cloudy water. If you don't know your volume, you cannot dose chemicals accurately.

  1. Select your pool shape: Choose from standard or complex freeform shapes.
  2. Measure the perimeter: Use a tape measure to find the maximum length and width of the water surface.
  3. Find your depths: Measure the water depth at the shallowest point and the deepest point. Our calculator will automatically do the math to find your average depth.
  4. Don't forget the spa: If you have an attached spa that shares the same water and plumbing as the pool, make sure to toggle it on so you get a true total system volume.

The Math & Science Behind the Tool

If you want to do the math manually, calculating pool volume requires two steps: finding the Cubic Volume, and then multiplying it by a conversion factor to get gallons or liters.

Rectangular Pools

Length × Width × Avg Depth = Cubic Ft

Once you have your cubic feet, multiply that number by 7.48 (the number of gallons in one cubic foot of water).

Freeform Pools

L × W × Avg Depth × 0.45 = Cubic Ft

For organic freeform shapes, the industry standard is to treat it like a rectangle, but multiply the final result by a 0.45 tolerance modifier to account for the curved edges.

Frequently Asked Questions

How do I calculate the average depth of my pool?

To find the average depth, measure the depth of the shallow end and the deep end. Add these two numbers together, and divide by two. Example: (3ft + 8ft) / 2 = 5.5 ft average depth.

What happens if my volume is wrong?

If you underestimate your volume, you will under-dose your chemicals, allowing algae to bloom. If you overestimate, you will waste money on excess shock and risk bleaching your pool liner or irritating swimmers' skin.

How do I measure a kidney pool?

Kidney pools are tricky. Measure the longest length, the widest width, and the narrowest width. Add the widest and narrowest widths together and divide by two to get an average width. Then use the standard rectangular formula with a 0.45 modifier.

Next Steps: Balance Your Water

Now that you know exactly how many gallons your pool holds, use our suite of free tools to calculate your exact chemical dosages.