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US Gallons to Liters

One US gallon equals 3.785412 liters.

Liters = US gallons × 3.785411784

Volume Conversion Calculator

Common Volume Conversions

Cooking & Baking Reference

Cooking Basics

  • 1 cup = 16 tablespoons = 48 teaspoons
  • 1 tablespoon = 3 teaspoons
  • 1 cup = 8 fluid ounces
  • 1 pint = 2 cups = 16 fluid ounces

Baking Conversions

  • 1 cup flour ≈ 120-125g
  • 1 cup sugar ≈ 200g
  • 1 cup butter ≈ 227g
  • 1 cup milk ≈ 240ml

International

  • 1 US cup = 236.588 ml
  • 1 UK cup = 284.131 ml
  • 1 metric cup = 250 ml
  • 1 Japanese cup = 200 ml

Volume Units Reference

Metric System

  • 1 m³ = 1,000 liters
  • 1 liter = 1,000 ml
  • 1 liter = 1 dm³
  • 1 ml = 1 cm³

US Customary

  • 1 gal = 4 quarts
  • 1 quart = 2 pints
  • 1 pint = 2 cups
  • 1 cup = 8 fl oz

Key Conversions

  • 1 US gal = 3.785 L
  • 1 UK gal = 4.546 L
  • 1 cup = 236.6 ml
  • 1 fl oz = 29.57 ml

US Gallons to Liters Conversion Table

gall
13.7854
27.5708
311.3562
518.9271
1037.8541
1245.4249
1556.7812
2075.7082
2594.6353
30113.5624
40151.4165
50189.2706
75283.9059
100378.5412
250946.3529

About This Conversion

US gallons to liters is needed for fuel economy, tank capacities and bulk liquids in any specification written for the American market. One US gallon is exactly 3.785411784 liters, a value that descends from the old English wine gallon of 231 cubic inches.

The imperial gallon still used in the UK for some purposes is a different unit at 4.54609 L, about 20 percent larger. That gap is why US and UK miles-per-gallon figures for the same car differ noticeably even though both are quoted as "mpg".

Frequently Asked Questions

How many liters are in a US gallon?

Exactly 3.785411784 liters, normally quoted as 3.785 L.

How many liters is 15 US gallons?

15 US gallons is 56.78 liters, a typical car fuel tank.

Is a UK gallon the same as a US gallon?

No. An imperial gallon is 4.546 L against the US gallon at 3.785 L, roughly 20 percent larger.

Why are US and UK mpg figures different?

Because the gallon differs. The same car scores about 20 percent higher mpg when measured in imperial gallons.

Worth Knowing

US Gallon vs Imperial Gallon

A US gallon is 3.785411784 litres and an imperial (UK) gallon is 4.54609 litres, making the imperial gallon about 20.1 percent larger.

Cup Sizes Explained

A US customary cup is 236.59 mL, a US legal cup is 240 mL, a metric cup is 250 mL and a historic imperial cup is 284 mL.

Fluid Ounce vs Ounce

A US fluid ounce is 29.5735 millilitres of volume, while an ounce is 28.3495 grams of mass; there is no fixed conversion between them.

Cups to Grams for Baking

One US cup holds about 125 g of plain flour, 200 g of granulated sugar, 227 g of butter and 340 g of honey.