Swimming Pool Sizes: Dimensions, Depths and Gallons
Standard sizes for in-ground, above-ground, lap and small pools, with surface area, water volume in gallons and liters, typical depths and the yard space each one really takes. Includes the formulas to work out your own pool's volume.
The classic residential in-ground pool is 16 × 32 ft (4.9 × 9.8 m), holding about 19,000 gallons (72,500 L) at an average depth of 5 ft. Common in-ground sizes run from 12 × 24 ft to 20 × 40 ft. Above-ground pools are mostly round, 12 to 33 ft (3.7 to 10 m) across with 48 to 54 in walls; an Olympic pool is 50 × 25 m.
- Classic in-ground
- 16 × 32 ft (4.9 × 9.8 m)
- Popular above-ground
- 18-24 ft round
- Above-ground walls
- 48, 52 or 54 in
- Olympic pool
- 50 × 25 m, 2 m+ deep
On this page
In-ground pool sizes
Most residential in-ground pools keep a 1:2 proportion of width to length, which leaves room to swim a few strokes and to play in the shallow end. Gallons below assume an average depth of 5 ft, for example a 3.5 ft shallow end sloping to about 6.5 ft. Use your own average depth in the formula further down for an exact figure.
| Size (ft) | Size (m) | Surface area | Gallons (5 ft avg) | Liters |
|---|---|---|---|---|
| 12 × 24 | 3.66 × 7.32 | 288 sq ft 26.8 m² | 10,800 | 40,800 |
| 14 × 28 | 4.27 × 8.53 | 392 sq ft 36.4 m² | 14,700 | 55,500 |
| 15 × 30 | 4.57 × 9.14 | 450 sq ft 41.8 m² | 16,800 | 63,700 |
| 16 × 32 | 4.88 × 9.75 | 512 sq ft 47.6 m² | 19,100 | 72,500 |
| 18 × 36 | 5.49 × 10.97 | 648 sq ft 60.2 m² | 24,200 | 91,700 |
| 20 × 40 | 6.10 × 12.19 | 800 sq ft 74.3 m² | 29,900 | 113,300 |
Fiberglass pools come as one-piece shells, so their sizes are limited by road transport: shells wider than about 16 ft (4.9 m) are rare. Vinyl-liner and concrete (gunite) pools can be built to any size and shape, including L-shapes, kidneys and freeforms.
Typical depths
- Shallow end: 3 to 3.5 ft (0.9 to 1.1 m), deep enough to swim, shallow enough for children to stand with an adult.
- Sport or play pool: 3.5 to 5 ft (1.1 to 1.5 m) throughout, with no deep end. Good for volleyball and families, not for diving.
- Deep end: 6 to 8 ft (1.8 to 2.4 m) on most home pools. Headfirst entry needs at least 9 ft (2.7 m) according to the American Red Cross.
Above-ground pool sizes
Above-ground pools are sold by diameter (round) or length × width (oval) and by wall height: 48, 52 or 54 in (122, 132 or 137 cm). Water sits about 6 in below the top, so a 52 in wall holds about 46 in (117 cm) of water. Gallons below use that 52 in wall.
| Diameter | Metric | Surface area | Gallons (52 in wall) | Liters |
|---|---|---|---|---|
| 12 ft | 3.66 m | 113 sq ft 10.5 m² | 3,200 | 12,300 |
| 15 ft | 4.57 m | 177 sq ft 16.4 m² | 5,100 | 19,200 |
| 18 ft | 5.49 m | 254 sq ft 23.6 m² | 7,300 | 27,600 |
| 21 ft | 6.40 m | 346 sq ft 32.2 m² | 9,900 | 37,600 |
| 24 ft | 7.32 m | 452 sq ft 42.0 m² | 13,000 | 49,100 |
| 27 ft | 8.23 m | 573 sq ft 53.2 m² | 16,400 | 62,100 |
| 30 ft | 9.14 m | 707 sq ft 65.7 m² | 20,300 | 76,700 |
| 33 ft | 10.06 m | 855 sq ft 79.5 m² | 24,500 | 92,800 |
| Size (ft) | Size (m) | Surface area | Gallons (52 in wall) |
|---|---|---|---|
| 12 × 24 | 3.66 × 7.32 | 257 sq ft 23.9 m² | 7,400 |
| 15 × 30 | 4.57 × 9.14 | 402 sq ft 37.3 m² | 11,500 |
| 18 × 33 | 5.49 × 10.06 | 524 sq ft 48.7 m² | 15,000 |
| 21 × 41 | 6.40 × 12.50 | 766 sq ft 71.2 m² | 22,000 |
Oval areas are for the usual straight-sided shape: a half circle at each end joined by straight walls. Ovals fit narrow yards better than rounds of the same water area, but need side buttresses, which add about 2 to 3 ft (60 to 90 cm) to the width on each side.
Inflatable, frame and stock tank pools
- Inflatable ring and frame pools run from about 8 to 24 ft (2.4 to 7.3 m) across, with walls of 30 to 52 in (76 to 132 cm). Rectangular frame pools come in sizes such as 9 × 18 ft and 12 × 24 ft.
- Stock tank pools are 6, 8 or 10 ft (1.8 to 3 m) round and 2 ft (61 cm) deep. An 8 ft tank holds about 750 gallons (2,850 L).
- Plunge pools are small in-ground or above-ground pools of about 7-10 × 10-20 ft (2-3 × 3-6 m), 4 to 6 ft deep, for cooling off rather than swimming.
How to calculate pool gallons
Every shape uses the same rule: surface area × average depth × 7.48, because one cubic foot holds 7.48 US gallons. In metric, area (m²) × average depth (m) × 1,000 gives liters.
- Find the average depth. Add the shallow and deep depths and divide by 2. For 3.5 and 6.5 ft, the average is 5 ft. For a flat-bottom above-ground pool, use the water depth.
- Find the surface area. Rectangle: length × width. Round: 0.785 × diameter². Straight-sided oval: 0.785 × width² + width × (length − width).
- Multiply. Area × average depth × 7.48. A 16 × 32 ft pool at 5 ft: 512 × 5 × 7.48 = 19,149 gallons.
- Convert if needed. Gallons × 3.785 = liters.
Pool chemicals are dosed per 10,000 gallons, and pumps are sized to circulate the whole volume in about 8 hours: gallons ÷ 480 gives the minimum flow in gallons per minute. A 16 × 32 ft pool needs about 40 gpm, an 18 ft round about 15 gpm.
Lap pools and competition pools
| Pool | Length | Width | Depth |
|---|---|---|---|
| Residential lap pool | 40-75 ft 12-23 m | 8-10 ft 2.4-3 m | 3.5-5 ft |
| Short course, yards (US schools, clubs) | 25 yd 22.86 m | Lanes about 7 ft 2.1 m wide | Varies by venue |
| Short course, meters | 25 m 82 ft | Lanes 2.5 m in international pools | Varies by venue |
| Olympic (long course) | 50 m 164 ft | 25 m 82 ft, 10 lanes × 2.5 m | 2 m minimum, 3 m recommended |
A 50 × 25 m pool holds 2,500 m³ (2.5 million liters, about 660,000 US gallons) at 2 m deep and 3,750 m³ at 3 m. In a home lap pool, 40 ft is about the shortest length that gives more than a few strokes per length; 8 ft of width allows one swimmer with arms clear of the walls.
How much yard space a pool needs
The water is only part of the footprint. Plan for:
- Deck or walkway: at least 3 to 4 ft (0.9 to 1.2 m) around in-ground pools, and 8 to 10 ft on the side where loungers go. A deck size guide covers raised decks beside above-ground pools.
- Setbacks: local zoning usually keeps pools 5 to 10 ft from property lines and away from septic fields, easements and overhead power lines.
- Equipment pad: about 4 × 8 ft (1.2 × 2.4 m) for pump, filter and heater, within about 50 ft of the pool.
- Fence line: the barrier can run along the deck edge or the yard boundary, but must be continuous.
Worked example: a 16 × 32 ft pool with a 4 ft deck all round covers 24 × 40 ft (960 sq ft, 89 m²). With a 10 ft setback on two sides it needs a clear area of about 34 × 50 ft.
The CPSC barrier guidelines and the ISPSC call for a fence or wall at least 48 in (1.22 m) high on the outside, gaps between pickets under 4 in (10 cm), no more than 2 in (5 cm) between the bottom and grass or gravel, and self-closing, self-latching gates. If the latch release is lower than 54 in (1.37 m), it must be on the pool side. An above-ground pool wall of 48 in or more can serve as the barrier if the ladder is removed or locked.
For covers sized to each of these pools, see the pool cover size guide. A hot tub is the compact alternative for small yards, and sauna dimensions covers the other common backyard wellness build. If you were looking for billiards, the pool table size chart has 7, 8 and 9 ft table dimensions and room sizes. Kids' backyard equipment such as trampolines needs its own clear zone away from the pool fence.
Frequently asked questions
How many people can a 24 ft round pool hold comfortably?
A 24 ft round pool has 452 sq ft (42 m²) of water. At a relaxed 25 to 35 sq ft per swimmer, that is about 13 to 18 people. Above-ground pools are about 4 ft deep all over, so the whole area is usable for standing play.
How big is an Olympic swimming pool?
50 m long and 25 m wide (164 × 82 ft), with ten 2.5 m lanes of which eight are used in finals. World Aquatics sets a minimum depth of 2 m and recommends 3 m. At 2 m deep it holds 2.5 million liters (about 660,000 US gallons).
How deep should a pool be for diving?
The American Red Cross advises at least 9 ft (2.7 m) of water for headfirst entry. Most residential pools are too shallow for diving anywhere, and diving boards on home pools need the depth and shape set by the board maker and local code.
Can a pool be too big for my yard?
Add a 3 to 4 ft deck on all sides, the local setback from property lines (often 5 to 10 ft) and space for the pump and filter. A 16 × 32 ft pool with a 4 ft deck occupies 24 × 40 ft before setbacks, about 960 sq ft (89 m²).
What size pump does a pool need?
Size the pump to turn over the whole volume in about 8 hours: gallons ÷ 480 = gallons per minute. A 19,000 gallon pool needs about 40 gpm; a 13,000 gallon 24 ft round pool about 27 gpm. Follow the filter's maximum flow rating as well.
Is there a standard pool fence height?
US guidance from the CPSC and the International Swimming Pool and Spa Code calls for a barrier at least 48 in (1.22 m) high, gaps under 4 in, no more than 2 in clearance at the bottom over grass, and self-closing, self-latching gates. Local codes can be stricter.