Calculate pool occupancy, code load, and volume from pool shape, dimensions, deck area, and water depth in feet or metres, with gallons and liters.

Pool Occupancy Calculator

Enter dimensions, choose a method, then calculate.

Max Occupancy
Code Load
Volume

Related Calculators

Pool Occupancy Formula

The pool occupancy calculator uses surface area as the starting point. The exact formula depends on the selected tab and pool shape.

Aᵣect = L * W
A_circle = pi * (D / 2)²
Aₖidney = 0.45 * (A + B) * L
Nₘax = floor((Aₘ2 / 3) * F)
N_code = round(Aₚool_ft2 / PF) + round(A_deck_ft2 / DF)
V_gal = A_ft2 * Dₐvg * 7.48052
  • A_rect = rectangular pool surface area
  • A_circle = circular pool surface area
  • A_kidney = estimated kidney or irregular oval pool surface area
  • L = length
  • W = width
  • D = diameter for a circular pool
  • A and B = the two measured widths of a kidney or irregular pool
  • A_m2 = pool water surface area in square meters
  • A_ft2 = pool water surface area in square feet
  • F = operating adjustment factor
  • N_max = recommended maximum pool water occupancy
  • N_code = code-style occupant load
  • A_pool_ft2 = pool surface area in square feet
  • A_deck_ft2 = pool deck area in square feet
  • PF = pool surface factor, usually entered as ft² per person
  • DF = deck area factor, usually entered as ft² per person
  • D_avg = average water depth in feet
  • V_gal = pool volume in gallons

The max occupancy mode starts at 3 m² of water surface per person, then applies operating adjustments. The adjustment factor is limited to a minimum of 50% and a maximum of 130%. Code load mode uses the pool and deck factors you enter. Local rules may require different factors.

Pool Occupancy Reference Tables

Use these values to check whether your result is in a reasonable range.

Use type Typical area factor What it means
General swimming estimate 3 m²/person Used as the starting point for recommended maximum water occupancy.
Pool surface code reference 50 ft²/person Common code-style reference for pool water surface load.
Pool deck code reference 15 ft²/person Common default for deck occupant load when the deck is used by bathers.
Condition Adjustment Effect on occupancy
Maximum depth below 1.35 m +10% Allows a higher estimate for non-swimming depth.
Adult leisure or relaxation session +5% Allows a small increase for lower activity intensity.
High child or family use -20% Reduces occupancy for higher supervision demand.
Diving, jumping, ball games, inflatables, or floating play -20% Reduces occupancy for higher-risk activity.
Freeform sides, scenery, or obstructions -10% Reduces occupancy where visibility and movement are less clear.

Using the Pool Occupancy Result

Treat the max occupancy result as a planning estimate, not a permit value. Use the code load result when you need a code-style occupant load based on entered ft²/person factors.

If your pool has unusual features, split the pool into simpler sections and enter the combined surface area directly. For posted limits, inspections, or licensing, use the rule required by your local authority.