Construction & Home

Pool Volume Calculator

Calculates the water volume of a rectangular pool from its length, width, and average depth in feet, reporting the result in cubic feet and in gallons.

What this calculator does

The Pool Volume Calculator estimates your result instantly from the values you enter, using standard construction & home formulas. Calculates the water volume of a rectangular pool from its length, width, and average depth in feet, reporting the result in cubic feet and in gallons. Calculations run in your browser, so nothing you type is sent to a server, and the output is an estimate rather than a certified or official figure.

Pool Volume Calculator

Result

—
Volume (ft³)
—
Capacity (gallons)

About Pool Volume Calculator

This pool volume calculator estimates how much water a rectangular pool holds. It multiplies length by width by average depth for the volume in cubic feet, then multiplies by 7.48052 gallons per cubic foot to get the capacity in gallons.

Using an average depth lets a pool that slopes from shallow to deep be estimated with a single figure.

Formula & Mathematical Calculation

Volume (ft³) = f(Length (ft), Width (ft), Average Depth (ft))

Calculated according to standard construction formulas implemented in the calculator core.

Calculation Example

For a pool 30 ft long, 15 ft wide, with a 5 ft average depth:

  • Volume = 30 × 15 × 5 = 2250 ft³
  • Capacity = 2250 × 7.48052 ≈ 16,831 gallons

Key Benefits

  • Reports pool capacity in both cubic feet and gallons
  • Uses average depth so sloped-floor pools can be estimated simply
  • Applies the standard 7.48052 gallons per cubic foot conversion
  • Gives a capacity figure useful for dosing and fill-time planning

How to Use this Calculator

  1. Enter the length
    Type the pool length in feet into the Length (ft) field, for example 30.
  2. Enter the width
    Type the pool width in feet into the Width (ft) field, for example 15.
  3. Enter the average depth
    Type the average water depth in feet into the Average Depth (ft) field, for example 5.
  4. Calculate
    Press Calculate to see the volume in cubic feet and the capacity in gallons.

Assumptions & Limitations

What the calculation assumes

  • Every value you enter is treated as an exact, known amount.
  • Any rate or interval you enter is assumed to hold for the whole period unless the form asks for it separately.
  • Results use standard published formulas and account only for the values entered above.
  • Rounding is applied for display; the underlying calculation uses your full precision.
  • Results are returned in the same units you enter, unless the tool states the output unit.

What it does not cover

  • Pool Volume Calculator produces a calculated result for reference and learning, not a certified or official measurement.
  • Real-world outcomes differ when tolerances, rounding rules or local standards apply.
  • Definitions and standards vary by region and change over time; verify the convention that applies to your case.
  • Figures are only as accurate as the inputs you supply — check them before acting on the result.
  • For work where the result carries real consequences, confirm it against an authoritative source.

Frequently Asked Questions

For a pool that slopes, use the average of the shallow and deep ends. For a flat-bottomed pool, use the single water depth.

The calculator multiplies the cubic-foot volume by 7.48052, the number of US gallons in one cubic foot.

It uses a rectangular length-by-width-by-depth formula, so it fits rectangular pools. Round or free-form shapes would need a different area calculation.

Free to use, no account needed. Calculations run in your browser, so nothing you type is sent to a server. Results are estimates — how we build and check our calculators.