Unit Conversion

Gallon Calculator

Enter any supported US volume unit and see gallons, liters, quarts, pints, and cups together.

Enter a volume

Choose the unit matching your value; US customary definitions are used.

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About this converter

How to use Gallon Calculator, plus the formulas and logic behind the results.

Tool description

The gallon calculator normalizes the input to US gallons and displays common metric and US customary equivalents.

How to use

  1. Enter the volume.
  2. Select its current unit.
  3. Select Calculate.
  4. Review every displayed equivalent.

Formulas & reference

  • 1 US gal = 3.785411784 L
  • 1 US gal = 4 qt = 8 pt = 16 cups
  • gallons = input × unit factor

Quick reference

  • 1 US gal = 3.785411784 L
  • 1 US gal = 4 qt = 8 pt = 16 cups
  • gallons = input × unit factor

Calculation logic

Each input unit is converted to US gallons, then multiplied by the appropriate factor for every output.

Results use standard stated conversion factors and may be rounded for display.

Gallon Calculator FAQ

Common questions about this conversion and how to interpret the result.

How many liters are in a US gallon?

One US gallon equals 3.785411784 liters.

How many quarts are in a gallon?

There are 4 US quarts in a US gallon.

How many pints are in a gallon?

There are 8 US pints in a US gallon.

How many cups are in a gallon?

There are 16 US cups in a US gallon.

Does this support UK gallons?

No. This calculator uses the US liquid gallon.

Can I start with liters or cups?

Yes. Select any listed input unit.