Convert Cubic inches to US gallons
1 cubic inch = 0.004329004 US gallons · gal = in³ ÷ 231
When you need this conversion
This conversion goes from cubic inches, used for engine displacement and small volumes, to US gallons, the fuel and liquid volume unit in the US. Both measure the same physical quantity, so the conversion is exact — the difference is which unit your source, tool, or region happens to use.
Cubic inches to US gallons conversion table
| Cubic inches (in³) | US gallons (gal) |
|---|---|
| 1 in³ | 0.004329004 gal |
| 2 in³ | 0.008658009 gal |
| 3 in³ | 0.012987 gal |
| 5 in³ | 0.021645 gal |
| 10 in³ | 0.04329 gal |
| 15 in³ | 0.064935 gal |
| 20 in³ | 0.08658 gal |
| 25 in³ | 0.108225 gal |
| 50 in³ | 0.21645 gal |
| 75 in³ | 0.324675 gal |
| 100 in³ | 0.4329 gal |
| 250 in³ | 1.0823 gal |
| 500 in³ | 2.1645 gal |
| 1,000 in³ | 4.329 gal |
The formula
gal = in³ ÷ 231Because both units measure volume, the conversion is a single multiplication by a fixed factor. That factor never changes, so the result is exact.
Convert the other way
US gallons to cubic inches →Related volume conversions
- Liters to US gallons
- Milliliters to US cups
- Milliliters to US fluid ounces
- Liters to cubic meters
- Cubic meters to liters
- Cubic meters to cubic feet
- Cubic feet to cubic meters
- US gallons to liters
- US cups to milliliters
- US fluid ounces to milliliters
- Milliliters to US gallons
- Cubic meters to US gallons
Frequently asked questions
- How many US gallons are in a cubic inch?
- There are 0.004329004 US gallons in 1 cubic inch. The formula is gal = in³ ÷ 231.
- How do you convert cubic inches to US gallons?
- Use the formula gal = in³ ÷ 231. For example, 10 cubic inches equals 0.04329 US gallons.
- Is the cubic inches to US gallons conversion exact?
- Yes. Cubic inches and US gallons are both units of volume, related by an exact defined factor. Displayed results are rounded for readability.
- What is in³ short for?
- in³ is the standard symbol for cubic inch. gal is the symbol for US gallon.