Gallons to Liters Converter

About Gallons → Liters

US paint cans, milk jugs, and pool chemicals quote gallons. Metric mixing instructions need liters. Converting US gallons to liters uses 3.785 L per gallon.

Specify US gallons unless form offers UK imperial.

Gallons in, liters out.

How to use this tool

Type gallons. Calculate for liters.

Formula & methodology

This gallons to liters converter applies the standard relationship below. Intermediate values are kept at full precision; only the displayed result is rounded.

L = US gal x 3.785411784

Tips for accurate results

• 1 US gallon is about 3.79 L.
• Reverse: liters-to-gallons.
• Fuel tank capacity labels may be approximate.
• Verify spill kit volumes after conversion.

Frequently asked questions

Sources & references

The factors and formulas used by this tool follow these references:

• NIST Special Publication 811 — Guide for the Use of the International System of Units (SI)
• BIPM — The International System of Units (SI Brochure, 9th edition)

Last reviewed: September 2026. Found an error? Tell us and we will correct it.