Pool Volume Calculator Examples: Different Shapes & Sizes

July 16, 2026

Three worked examples below, using the same formulas the pool volume calculator runs. For term definitions, see the pool volume terms glossary.

Example 1 — Flat-Bottom Rectangular Above-Ground Pool

24 × 12 ft, flat 4.5 ft depth throughout

24 × 12 × 4.5 × 7.5 = 9,720 gallons

Flat-bottom pools (common for above-ground installs) skip the average-depth step entirely, since there’s only one depth to measure.

Example 2 — Large Round In-Ground Pool

24 ft diameter, flat 4.5 ft depth

Radius = 24 ÷ 2 = 12 ft
3.14159 × 12² × 4.5 × 7.5 = 15,268 gallons

Notice the radius (12 ft), not the diameter (24 ft), goes into the formula — using diameter directly instead of dividing by 2 first would overestimate this pool’s volume by roughly 4x. See common pool volume calculation mistakes for how often this specific error happens.

Example 3 — Sloped Oval In-Ground Pool

18 × 36 ft, 3 ft shallow end / 8.5 ft deep end

Avg. Depth = (3 + 8.5) ÷ 2 = 5.75 ft
18 × 36 × 0.785 × 5.75 × 7.5 = 21,937 gallons

This is a larger, deeper pool than the round example, and the sloped-bottom average-depth step is essential here — using the 8.5 ft deep-end figure alone instead of the 5.75 ft average would overstate the true volume by nearly 50%.

Scaling a Chemical Dose From Example 1

Using the 9,720-gallon flat-bottom pool from Example 1, and a liquid chlorine product labeled “10 fl oz per 1 ppm per 10,000 gallons”:

Dose = (9,720 ÷ 10,000) × 10 fl oz = 9.72 fl oz per 1 ppm increase

See pool volume calculator for chemical dosing for the full scaling method and typical dosing ranges for other common pool chemicals.

Try Your Own Pool

Enter your pool’s actual shape, dimensions, and depth into the pool volume calculator — if your pool doesn’t match a simple rectangle, circle, or oval, see how to measure an irregular or freeform pool for volume for the sectioning method.