Convert US Gallon to Litre

Quick answer: US Gallon to Litre

1 US Gallon = 3.785412 Litre (US gal → L). To convert us gallon to litre, multiply by 3.785412. To convert litre to us gallon, multiply by 0.2641721. The converter at the top does this instantly and both ways; the sections below give the formula, worked examples, a full conversion chart and answers to the most common us gallon-to-litre questions.

How to convert US Gallon to Litre

To convert us gallon to litre, multiply the number of us gallon by the conversion factor 3.785412, because 1 US gal = 3.785412 L. The conversion is linear, so the same factor works for any value — whole numbers, decimals or fractions. For the reverse direction, 1 L = 0.2641721 US gal, so you divide by 3.785412 (or multiply by 0.2641721) to turn litre back into us gallon.

L = US gal × 3.785412  ·  US gal = L × 0.2641721

1. Write down the value you want to convert, in us gallon.
2. Multiply it by 3.785412.
3. The result is the same area/length/quantity expressed in litre.

US Gallon to Litre — worked examples

Each row shows the exact arithmetic so you can follow the conversion step by step. For example, 5 us gallon is 18.92706 litre because 5 US gal × 3.785412 = 18.92706 L.

Common US Gallon to Litre conversions

These are the us gallon-to-litre values people look up most often. Every figure is computed from the exact factor, so you can rely on them for quick reference:

• 1 us gallon = 3.785412 litre
• 2 us gallon = 7.570824 litre
• 2.5 us gallon = 9.463529 litre
• 3 us gallon = 11.35624 litre
• 4 us gallon = 15.14165 litre
• 5 us gallon = 18.92706 litre
• 6 us gallon = 22.71247 litre
• 7 us gallon = 26.49788 litre
• 8 us gallon = 30.28329 litre
• 9 us gallon = 34.06871 litre
• 10 us gallon = 37.85412 litre
• 12 us gallon = 45.42494 litre
• 15 us gallon = 56.78118 litre
• 20 us gallon = 75.70824 litre
• 25 us gallon = 94.63529 litre
• 30 us gallon = 113.5624 litre
• 50 us gallon = 189.2706 litre
• 75 us gallon = 283.9059 litre
• 100 us gallon = 378.5412 litre
• 200 us gallon = 757.0824 litre
• 500 us gallon = 1,892.706 litre
• 1000 us gallon = 3,785.412 litre

US Gallon to Litre conversion chart (both directions)

The chart below converts us gallon to litre and litre to us gallon side by side, so it works whichever way you need. 1 us gallon = 3.785412 litre, and 1 litre = 0.2641721 us gallon.

US Gallon vs Litre: which is bigger?

A us gallon is the larger unit: one us gallon equals 3.785412 litres. Put another way, you need 3.785412 litres to make a single us gallon.

What is a US Gallon? History, origin and usage

The US gallon descends from the British Queen Anne wine gallon, fixed by statute in 1706 as exactly 231 cubic inches and brought into force in 1707; the young United States kept this measure and adopted it formally in 1836. Britain, meanwhile, abolished the wine gallon and replaced it with the larger imperial gallon in 1824, which is why the two gallons differ today.

The US gallon is the standard American unit for selling fuel, milk, paint and many household liquids, and fuel economy is reported in miles per gallon. It is used across the United States and in a handful of countries influenced by American trade.

The US gallon is noticeably smaller than the imperial gallon used in the UK and Canada, a roughly one-fifth difference that catches out travellers comparing fuel prices. Its size is frozen at the 1707 Queen Anne standard, while Britain reformed away from it.

What is a Litre? History, origin and usage

The litre was introduced in France in 1795 as a republican measure equal to one cubic decimetre, its name derived from the older French litron, in turn from Byzantine Greek (where it had been a unit of weight) via Late Medieval Latin. In 1901 the litre was redefined as the volume of one kilogram of pure water at maximum density, making it very slightly larger than a cubic decimetre. In 1964 that awkward definition was abandoned and the litre returned to being exactly one cubic decimetre.

The litre is the everyday metric unit of volume across most of the world: fuel sold at the pump, bottled water and soft drinks, milk, engine and cooking oil, and car engine capacity. It is the unit people reach for whenever a volume is larger than a kitchen spoonful but smaller than a tankful.

The litre is not an official SI unit but is accepted for use alongside it. Its symbol may be written as a capital L precisely because a lowercase l is easily mistaken for the digit 1 in many fonts.

Convert 1 US Gallon to other units

It can help to see a us gallon next to the other units it is commonly compared with. One us gallon (US gal) is equal to:

Convert 1 Litre to other units

One litre (L) is equal to:

Tips for converting US Gallon to Litre

• To go from us gallon to litre, multiply by 3.785412; to go back, divide by 3.785412 (or multiply by 0.2641721).
• For a quick mental estimate, remember that 1 us gallon ≈ 3.785412 litre, so 10 us gallon ≈ 37.85412 litre.
• The converter above keeps full precision; the tables round for readability, so use the tool for exact figures.
• Both fields update live as you type — change either side to convert in that direction.

How to use this US Gallon to Litre converter

Type a number into the US Gallon field and the equivalent in Litre appears instantly — there is no “convert” button to press and nothing is sent to a server, so it works offline once the page has loaded and is safe for any data. You can also type into the Litre field to convert the other way (litre to us gallon). Use the swap control to flip the two units, and copy the result with a single click. Because the calculation runs in your browser with full floating-point precision, the converter is more exact than the rounded figures shown in the reference chart above — use the chart for quick look-ups and the tool for precise work.

Accuracy and method

Every figure on this page — the formula, the worked examples, the conversion chart and the “convert to other units” tables — is computed from a single verified conversion factor (1 US gal = 3.785412 L), never copied from a hand-typed lookup table that could drift. That factor is derived from each unit’s definition in terms of a common base unit, and an automated check re-verifies all of the site’s factors on every update, so the numbers here stay correct over time. This matters for us gallon-to-litre conversions because a small rounding error in a published table compounds quickly at larger quantities; computing from the exact factor avoids that.

Sources

• NIST Special Publication 811 — Guide for the Use of the SI — publishes the exact metric equivalents of the customary units. The inch, foot, yard and mile are defined exactly in metres by the 1959 international yard-and-pound agreement, so every imperial figure on this page is exact, not rounded.
• BIPM — The International System of Units (SI Brochure) — the defining document for the SI, published by the International Bureau of Weights and Measures. It fixes the base unit that this conversion resolves to, which is why the factor here can be exact rather than approximate.

Watch the system: a <strong>US</strong> gallon, quart, pint and fluid ounce are <strong>not</strong> the same size as the <strong>imperial (UK)</strong> ones — a US gallon is 3.785 L while an imperial gallon is 4.546 L, and a US fluid ounce (29.57 mL) is slightly larger than an imperial fluid ounce (28.41 mL). The units on this page are labelled US or Imperial so the result is unambiguous.

Frequently asked questions

How many litre are in 1 us gallon?

1 us gallon = 3.785412 litre (L). To convert any number of us gallon to litre, multiply by 3.785412.

How do I convert us gallon to litre?

Multiply the number of us gallon by 3.785412. For example, 10 us gallon = 10 × 3.785412 = 37.85412 litre, and 25 us gallon = 94.63529 litre.

How many us gallon are in 1 litre?

1 litre = 0.2641721 us gallon. So to convert litre back to us gallon, multiply by 0.2641721.

What is the formula to convert us gallon to litre?

litre = us gallon × 3.785412. The reverse formula is us gallon = litre × 0.2641721.

How much is 100 us gallon in litre?

100 us gallon = 378.5412 litre. (And 1000 us gallon = 3,785.412 litre.)

Which is bigger, a us gallon or a litre?

A us gallon is larger: 1 us gallon = 3.785412 litre.

Is this us gallon to litre converter accurate?

Yes — every value is computed from the exact 3.785412 L per US gal factor (not rounded look-up tables), and the factors are re-verified automatically on every update.

Can I convert litre to us gallon too?

Yes. The converter works both ways — enter a value in either field. 1 litre = 0.2641721 us gallon.

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