Convert US Gallons to Cubic Centimeters

Formula

cm³ = gal (US) × 3785.411784

Derivation from SI units:

• 1 US gal = 231 in³ = 231 × (0.0254 m)³ = 0.003785411784 m³
• 1 cm³ = (0.01 m)³ = 10⁻⁶ m³ = 1 mL
• 1 gal (US) = 0.003785411784 m³ ÷ 0.000001 m³ per cm³ = 3785.411784 cm³

Both units are defined exactly, so the factor is exact. US Gallon definition: US gallon; Cubic Centimeter definition: cubic centimeter.

Worked examples

1. A reading of 10 gal (US) converts to 37854.11784 cm³.
   10 gal (US) × 3785.411784 = 37854.11784 cm³
2. A value of 100 gal (US) is 378541.1784 cm³.
   100 gal (US) × 3785.411784 = 378541.1784 cm³

Where it's used

US Gallons are used for fuel, water and chemical volumes in the US, while cubic centimeters appear in engine displacement (e.g. 125 cc, 1600 cc). Both measure volume (capacity), so the conversion is a fixed factor.

US Gallon to other volume units

Frequently asked questions

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 with SI prefix centi.

Last reviewed: 2026-10-15. Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.