Volume by water depth
| Water depth | US gallons | Litres |
|---|---|---|
| 34 in of water | 3,750 gal | 14,180 L |
| 36 in of water | 3,970 gal | 15,010 L |
| 38 in of water | 4,190 gal | 15,850 L |
Formula: 15 × 15 × 3 ft × 5.87 = 3,966 gal.
How many gallons is a 15 ft round × 42 in above-ground pool?
A 15 ft round above-ground pool with 42 in walls holds about 3,970 US gallons (15,010 L) when filled to 36 in of water, about 6 in below the top rail. Volume depends on the water depth, not the wall height, so measure your water and check the table.
Measure your own water depth
3,966gal
About 15,012 L
Average depth 3 ft
Formula: diameter² × average depth × 5.87.
- Pool shapes are never perfect. Treat this as within about 10%, and check it once by adding a known amount of salt or stabilizer and testing the change.
- Use this volume: Chlorine pH Shock All-in-one
Save this test and get reminded when it is time to retest.
Pool Calc for iPhoneComing soon to the App StoreDoses for this pool
| Job | Amount |
|---|---|
| Raise chlorine 1 ppm | 5.1 fl oz of 10% liquid chlorine |
| Stabilizer 0 → 30 ppm | 1 lb |
| Salt 0 → 3,200 ppm | 107 lb (2.7 bags) |
Full dose tables for a pool this size: liquid chlorine for 5,000 gallons, salt and stabilizer. Or put 3,966 gallons straight into the pool chemical calculator.
Check the number once
Manufacturer capacities are usually given at a stated fill level, and liners stretch. To confirm your real volume, add a known amount of salt or stabilizer and see how much the test reading moves: the volume that explains that change is your pool.
Questions
How many gallons does a 15 ft round × 42 in pool hold?
About 3,970 gallons at 36 in of water.
How many litres is a 15 ft round × 42 in pool?
About 15,010 L at 36 in (91 cm) of water.