USA Gallons to Liters Converter

This tool converts volume from US liquid gallons (gal) to liters (L) using the exact legal factor. Systems: US customary (US gal) and SI (L, mL). The math is shown for verification and is based on the official US definition of the gallon.

US Gallons (gal) to Liters (L) Converter

Enter a value in the field below and press the button

US Gallons (gal)

Result in Liters (L)

L to gal

Calculation process will appear here.

Decimal Places

Share this?

How to use

Enter the value in US gallons.
Optionally set decimal places for the result.
Select Convert to get liters and a step-by-step calculation line.
Use Copy Result to place the value on your clipboard.
Use Clear All to reset inputs.
The Swap button links to the inverse tool.

Definitions of measurement units

US liquid gallon (gal, US customary) — Exactly 231 cubic inches. With 1 inch defined as exactly 2.54 centimeters, 1 US gal equals 3.785411784 liters. Abbreviation: gal. System: US customary. In SI terms: 1 US gal = 3.785411784 L = 3785.411784 mL.

Liter (L, SI) — Exactly 1 cubic decimeter. 1 L = 1000 milliliters (mL) and 1 L = 0.001 cubic meter (m³). In US customary terms: 1 L = 0.264172052 US gal.

Conversion formula

US gallons to liters: L = gal × 3.785411784. Inverse: gal = L ÷ 3.785411784. Source: NIST Handbook 44, Appendix C (1 US gallon = 231 in³; 1 inch = 2.54 cm exact). NIST HB 44 Appendix C

Conversion table — US gallons to liters

US gal	L
0.25	0.946
0.50	1.893
0.75	2.839
1.00	3.785
1.25	4.732
1.50	5.678
1.75	6.624
2.00	7.571
2.25	8.517
2.50	9.464
2.75	10.410
3.00	11.356
3.25	12.302
3.50	13.248
3.75	14.195
4.00	15.142
4.25	16.088
4.50	17.034
4.75	17.981
5.00	18.927