Convert US Gallons to Cubic Meters
1 US gallon (gal (US)) equals 0.003785411784 cubic meters (m³).
1 gal (US) = 0.003785411784 m³
Type in either box. Scientific notation works: 1.5e-3.
Converting a list? Use the bulk US gallon to cubic meter converter to paste a column from Excel.
How to Convert US Gallon to Cubic Meter
- 1 gal (US) = 0.003785411784 m³
- 1 m³ = 264.1720524 gal (US)
- Example: convert 15 gal (US) to m³: 15 gal (US) = 15 × 0.003785411784 m³ = 0.05678117676 m³
Formula
m³ = gal (US) × 0.003785411784
or m³ = gal (US) ÷ 264.1720523581
Derivation from SI units:
- 1 US gal = 231 in³ = 231 × (0.0254 m)³ = 0.003785411784 m³
- 1 m³ = 1 m × 1 m × 1 m
Both units are defined exactly, so the factor is exact. US Gallon definition: US gallon; Cubic Meter definition: cubic meter.
Worked examples
- 1000 gal (US) of water is 3.785411784 m³.
1000 gal (US) × 0.003785411784 = 3.785411784 m³ - A 20000 gal (US) swimming pool holds 75.70823568 m³.
20000 gal (US) × 0.003785411784 = 75.70823568 m³
US Gallon to Cubic Meter conversion table
| US Gallons (gal (US)) | Cubic Meters (m³) |
|---|---|
| 0.25 gal (US) | 0.000946352946 m³ |
| 0.5 gal (US) | 0.001892705892 m³ |
| 1 gal (US) | 0.003785411784 m³ |
| 2 gal (US) | 0.007570823568 m³ |
| 2.5 gal (US) | 0.00946352946 m³ |
| 5 gal (US) | 0.01892705892 m³ |
| 10 gal (US) | 0.03785411784 m³ |
| 15 gal (US) | 0.05678117676 m³ |
| 20 gal (US) | 0.07570823568 m³ |
| 25 gal (US) | 0.0946352946 m³ |
| 50 gal (US) | 0.1892705892 m³ |
| 55 gal (US) | 0.2081976481 m³ |
| 100 gal (US) | 0.3785411784 m³ |
| 275 gal (US) | 1.040988241 m³ |
| 330 gal (US) | 1.249185889 m³ |
| 500 gal (US) | 1.892705892 m³ |
| 1000 gal (US) | 3.785411784 m³ |
| 10000 gal (US) | 37.85411784 m³ |
Where it's used
Large US volumes are converted to m³ for engineering calculations, water treatment and international projects.
US Gallon to other volume units
| Conversion | 1 gal (US) equals |
|---|---|
| US gallon to cubic meter | 0.003785411784 m³ |
| US gallon to liter | 3.785411784 L |
| US gallon to milliliter | 3785.411784 mL |
| US gallon to cubic centimeter | 3785.411784 cm³ |
| US gallon to cubic foot | 0.1336805556 ft³ |
| US gallon to cubic inch | 231 in³ |
| US gallon to imperial gallon | 0.8326741846 gal (imp) |
Frequently asked questions
How many m³ is 1000 gallons?
1000 US gal = 3.785411784 m³.
How many cubic meters are in 1 US gallon?
1 gal (US) = 0.003785411784 m³.
How do I convert US gallons to cubic meters?
Multiply the value in gal (US) by 0.003785411784, or divide it by 264.1720524. For example, 15 gal (US) × 0.003785411784 = 0.05678117676 m³.
Is the gal (US) to m³ conversion exact?
Yes. Both units are defined exactly, and 1 gal (US) is exactly 0.003785411784 m³.
Sources
- Guide for the Use of the International System of Units (SI), NIST Special Publication 811, 2008 Edition, National Institute of Standards and Technology , Appendix B.8, "gallon [U.S.] (gal)".
- NIST Handbook 44, Appendix C: General Tables of Units of Measurement, National Institute of Standards and Technology , Appendix C.
- The International System of Units (SI), 9th edition (SI Brochure), Bureau International des Poids et Mesures , Table 2, coherent derived units.
Last reviewed: . Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.
Cite this page
APA
Scientific Converters. (2026, October 15). Convert US Gallons to Cubic Meters. Retrieved October 17, 2026, from https://scientificconverters.com/volume/us-gallons-to-cubic-meters/
IEEE
Scientific Converters, "Convert US Gallons to Cubic Meters," scientificconverters.com. Accessed: Oct. 17, 2026. [Online]. Available: https://scientificconverters.com/volume/us-gallons-to-cubic-meters/