AI Calculator Tool

Gallons to Liters Converter

Convert US gallons to liters instantly. Free online gal to L calculator—multiply by 3.78541. For fuel, cooking, and aquariums.

How to Convert Gallon to Liter

To convert gallons to liters, multiply the number of gallons by 3.78541, as one gallon equals approximately 3.78541 liters.

Conversion Formula:

value * 3.78541

Conversion Examples

Example: 1 gallon to liters

  1. 1 × 3.78541 ≈ 3.785 L

1 US gallon ≈ 3.785 liters

Standard US liquid gallon.

Example: 15 gallons to liters

  1. 15 × 3.78541 ≈ 56.78 L

15 US gallons ≈ 56.78 liters

Typical fuel tank size context.

Conversion Chart

GallonLiter
13.785
27.571
311.356
415.142
518.927
622.712
726.498
830.283
934.069
1037.854
1556.781
2075.708
30113.562
60227.125
100378.541

Conversion Formula

The formula to convert gallon to liter is:

gallon × 3.78541 = liter

Mathematically, you can write this as:


gallon × 3.78541 liter/gallon = liter

The gallon units cancel out, leaving you with liter.

Quick Conversion Tip

Quick conversion: Multiply gallon by 3.78541 to get liter. For example, 1 gallon = 3.78541 liter, 2 gallon = 7.57082 liter, 5 gallon = 18.92705 liter.

Unit Definitions

US Gallon (gal)

A US gallon is a common liquid volume unit used in the United States for fuel, beverages, and water.

1 US gallon = 3.78541 liters = 128 US fluid ounces = 16 US cups

Liter (L)

A liter is a metric volume unit equal to one cubic decimeter. It is widely used for beverages, science, and everyday measurements.

1 liter = 0.001 cubic meter ≈ 61.0237 cubic inches ≈ 0.264172 US gallons

Common Use Cases

  • Fuel volume when traveling in metric countries.
  • Cooking and brewing recipes using liters.
  • Aquarium and chemical mixing labels.
  • Comparing US product volumes to metric packaging.

Understanding the Conversion

US gallons to liters uses 1 US gal = 3.785411784 L. Do not confuse with the larger imperial (UK) gallon (~4.546 L).

This page is for US liquid gallons—common for gas pumps, milk jugs, and pool chemicals in the United States.

FAQs

How many liters in a US gallon?

About 3.785 liters per US gallon.

Is a UK gallon the same?

No—an imperial gallon is about 4.546 liters.

How do I convert gallons to liters?

Multiply US gallons by 3.78541.