Kiddie pool gallons calculator
Measure the inside of the pool and how deep you fill it. Kiddie pools are small enough to fill in minutes — and the CDC says they should be emptied at least daily rather than treated with chemicals.
Enter your measurements
More options: Flow
- Water surface
- 18.3 sq ft
- Minutes to fill
- 14 minutes
- Weight of the water
- 859 lb
3.1416 × (58 in ÷ 2)² = 18 sq ft
× 9 in deep = 23,779 cu in ÷ 231 = 103 gal
÷ 7.5 gal a minute = 14 minutes
- Inflatable pools with sloping or rounded sides hold less than a straight-sided box of the same size — Intex’s listed figure for its 58 in pool is about 16% below this estimate.
Quick answers for common sizes
| Example | Answer |
|---|---|
| How many gallons in a kiddie pool | 103 gal |
Gallons at the size above, by water depth
| Depth | Gallons of water | Minutes to fill |
|---|---|---|
| 4 in | 46 gal | 6 minutes |
| 6 in | 69 gal | 9 minutes |
| 8 in | 92 gal | 12 minutes |
| 10 in | 114 gal | 15 minutes |
| 12 in | 137 gal | 18 minutes |
Kiddie pools hold far less than people expect — usually under 150 gallons — which is exactly why they are meant to be filled fresh and emptied, not treated like a backyard pool. The calculator works from the inside size and the depth you fill to.
How it works
round: 3.1416 × (inside diameter ÷ 2)² × water depth rectangle: inside length × width × water depth gallons = cubic inches ÷ 231 (litres = cubic cm ÷ 1,000)
What makers list
| Pool | Size | Listed capacity |
|---|---|---|
| Intex Rainbow Ombre inflatable kiddie pool | 58 in × 13 in | 87 gal at 9 in of wall height |
| Intex My Sea Friends inflatable kiddie pool | 64 × 42 × 18 in | 61 gal at 11 in of wall height |
| Intex Tropical Swim Center family pool | 90 × 60 × 19 in | 159 gal at 13 in of wall height |
Compare those with the straight-sided estimate: a 58 in round pool filled 9 in deep comes out at about 103 gallons in the calculator, while Intex lists 87. The difference is the thick, rounded inflatable ring — the inside diameter at the water line is smaller than the outside size printed on the box. Measure inside the ring for a closer number. The worked example is how many gallons in a kiddie pool.
Keeping kiddie-pool water safe
- Empty it at least daily. The CDC’s guidance for inflatable and plastic kiddie pools is to empty them at least once a day and let them dry, to help stop the spread of germs.
- Don’t add chlorine or bromine. The CDC says it is unsafe to add germ-killing disinfectants to kiddie pools. Pool chemical doses on this site are for filtered pools and hot tubs only.
- Keep sick kids out. Children with diarrhea or vomiting should stay out of the water.
- After an accident, drain and clean the pool, then follow the CDC’s steps for disinfecting the empty pool.
- Supervise. Even a few inches of water is enough for a toddler to drown.
Graduating to a small frame pool? See how many gallons in a 12x30 pool — those are filtered and can be chlorinated, using the liquid chlorine calculator.
What you’ll need
- Leaf skimmer netBudget price
Leaves and debris use up chlorine as they break down; netting them out first saves chemical.
See options on Amazon (opens in a new tab) - Hose water flow meterBudget price
Screws onto the hose and counts gallons, so you know exactly how much went in — and your real fill rate.
See options on Amazon (opens in a new tab) - Pool test stripsBudget price
Quick daily checks. Fine for spotting a trend; use a drop kit when you’re about to add a big dose or shock.
See options on Amazon (opens in a new tab)
As an Amazon Associate we earn from qualifying purchases. Links to products are affiliate links — they cost you nothing extra and help keep these calculators free.
Frequently asked questions
Can I put chlorine in a kiddie pool?
The CDC says no: it is unsafe to add germ-killing disinfectants such as chlorine or bromine to inflatable or plastic kiddie pools. Empty the pool at least daily and let it dry instead.
How long does a kiddie pool take to fill?
At 7.5 gallons a minute (an example — time how long your hose takes to fill a bucket), a 100-gallon kiddie pool fills in about 13 minutes.
How much does the water in a kiddie pool weigh?
About 8.34 lb per gallon — so 100 gallons is about 834 lb. That is why you shouldn’t set one up on a deck without checking it can carry the load, and why they are hard to move once full.
Sources
- CDC Healthy Swimming — Inflatable and plastic kiddie pools (opens in a new tab) — Empty kiddie pools at least daily; it is unsafe to add chlorine or bromine to them.
- Intex Rainbow Ombre inflatable kiddie pool — product page (opens in a new tab) — 58 in × 13 in; 87 gal at 9 in of wall height.
- Intex My Sea Friends inflatable kiddie pool — product page (opens in a new tab) — 64 × 42 × 18 in; 61 gal at 11 in of wall height.
- Intex Tropical Swim Center family pool — product page (opens in a new tab) — 90 × 60 × 19 in; 159 gal at 13 in of wall height.
- NIST Handbook 44, Appendix C (opens in a new tab) — 1 US gallon = 231 cubic inches.