Gallons to Liters Converter

1 US gallon = 3.785 liters

1 Gallon =
3.785
liters (L)
Exact: 1 US gal = 3.785411784 L
5 gal18.927 L
10 gal37.854 L
20 gal75.708 L
100 gal378.54 L
gal =L

How to Convert Gallons to Liters

Liters = Gallons × 3.785411784
1 US gallon = 3.785411784 liters (exact, defined since 1959)
Gallons = Liters × 0.264172
To convert liters back to US gallons
1 gallon in liters3.785 L
5 gallons in liters18.927 L
10 gallons in liters37.854 L
1 liter in gallons0.264172 gal
💡

Quick estimate: 1 US gallon ≈ 3.8 liters. For gas station math: multiply gallons by 3.8 for a close approximation. The exact factor is 3.785411784.

Gallons to Liters Reference Table

Gallons (gal)Liters (L)Quarts
0.5 gal1.893 L2 qt
1 gal3.785 L4 qt
1.5 gal5.678 L6 qt
2 gal7.571 L8 qt
2.5 gal9.464 L10 qt
3 gal11.356 L12 qt
4 gal15.141 L16 qt
5 gal18.927 L20 qt
6 gal22.712 L24 qt
7 gal26.498 L28 qt
8 gal30.283 L32 qt
9 gal34.069 L36 qt
10 gal37.854 L40 qt
15 gal56.781 L60 qt
20 gal75.708 L80 qt
25 gal94.635 L100 qt
30 gal113.562 L120 qt
50 gal189.271 L200 qt
100 gal378.541 L400 qt

Frequently Asked Questions

How many liters in a gallon?

1 US gallon = 3.785411784 liters exactly. For everyday use: 1 gallon ≈ 3.785 liters or approximately 3.8 liters.

How many liters is 5 gallons?

5 gallons = 18.927 liters. Multiply 5 × 3.785411784 = 18.927 liters. A standard 5-gallon water jug holds about 18.9 liters.

US gallon vs UK gallon — what's the difference?

US gallon = 3.785 liters. UK imperial gallon = 4.546 liters. The UK gallon is about 20% larger. Always specify which gallon you mean for international contexts.

How many gallons is 40 liters?

40 liters = 10.567 US gallons. Divide by 3.785411784: 40 ÷ 3.785 = 10.567 gallons.

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