Convert US gallons to liters easily.
1 gal x 3.78541 = 3.78541 L
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Ever tried following a European recipe only to find it uses liters instead of gallons? Or maybe you’ve compared car fuel efficiency ratings across countries and felt like you needed a decoder ring? You’re not alone. Converting between US gallons and liters trips up travelers, cooks, and engineers alike. But here’s the good news: once you understand the relationship between these units, you’ll navigate them as smoothly as a barista pulling espresso shots.
Unit definitions
What is a US gallon (gal)?
The US gallon is the underdog of liquid measurements – it’s primarily used in the United States while the rest of the world moved on to liters. Here’s the lowdown:
- Symbol: gal
- Common uses: Fuel economy ratings, beverage containers, swimming pool volumes
- Definition: Exactly 231 cubic inches or about 3.785 liters. Fun fact: this measurement originated from English wine gallons in the 18th century.
What is a liter (L)?
The liter is the metric system’s answer to liquid measurement, adopted by 95% of the world’s population. Key details:
- Symbol: L (capitalized to avoid confusion with the number 1)
- Common uses: Beverage labeling, medical dosages, engine displacements
- Definition: 1 cubic decimeter (0.001 cubic meters). It was originally defined in 1795 as the volume of 1 kilogram of water at 4°C.
Conversion formula
The magic number you need is 3.78541. Here’s how the math works:
Gallons to liters:
Liters = Gallons × 3.78541
Liters to gallons:
Gallons = Liters ÷ 3.78541
This conversion factor comes straight from the International Yard and Pound Agreement of 1959. It’s precise enough for NASA engineers but simple enough for your next barbecue recipe.
Example calculations
- Converting 5 gallons to liters:
5 gal × 3.78541 = 18.92705 L
Rounded to four decimals: 18.9271 L - Converting 20 liters to gallons:
20 L ÷ 3.78541 ≈ 5.28344 gal
Rounded to four decimals: 5.2834 gal
Conversion tables
US gallons to liters
| Gallons | Liters |
|---|---|
| 1 | 3.7854 |
| 2 | 7.5708 |
| 3 | 11.3562 |
| 4 | 15.1416 |
| 5 | 18.9271 |
| 6 | 22.7125 |
| 7 | 26.4979 |
| 8 | 30.2833 |
| 9 | 34.0687 |
| 10 | 37.8541 |
Liters to US gallons
| Liters | Gallons |
|---|---|
| 1 | 0.2642 |
| 2 | 0.5284 |
| 3 | 0.7925 |
| 4 | 1.0567 |
| 5 | 1.3209 |
| 6 | 1.5850 |
| 7 | 1.8492 |
| 8 | 2.1134 |
| 9 | 2.3775 |
| 10 | 2.6417 |
Historical background
The story of these units reads like a geopolitical drama. The US gallon traces its roots to 18th-century British wine measurements, standardized in 1707 under Queen Anne. When the Americans broke free, they kept the gallon but tweaked it slightly, because why make things simple, right?
The liter entered the scene during the French Revolution’s metric system overhaul in 1795. Scientists wanted measurements based on nature, not royal decrees. The original liter was carved from platinum, stored under lock and key near Paris. Today’s definition ties it to the meter, which itself is based on the speed of light – talk about an upgrade!
Here’s where it gets ironic: the US officially adopted the metric system in 1866 with the Metric Act. But try telling that to gas station pumps in Texas. The gallon persists due to infrastructure costs and, let’s be honest, sheer stubbornness.
Interesting facts
- Milk jug math: That gallon of milk in your fridge? It contains exactly 3.785 liters – same as a US liquid gallon.
- Fuel fight: European cars boast liters per 100 km, while Americans prefer miles per gallon. Converting between them requires more math than you’d expect.
- Swimming in units: Olympic pools hold 2,500,000 liters. In US gallons? That’s 660,430 – a number that’s harder to remember.
- Gasoline oddity: Crude oil is priced per barrel (42 US gallons), but refined gasoline sells in liters globally. Middlemen love this complexity.
- The great soda split: A 2-liter bottle contains 0.528 gallons. That’s why US soda cans often use fluid ounces instead.
FAQ
The US customary system evolved from British imperial units. While most countries switched to metric, the US retained gallons for liquid measurements due to tradition and infrastructure costs.
Multiply gallons by 3.8 for a rough estimate. For example, 2 gallons ≈ 7.6 liters. For precise calculations, use 3.78541 as the conversion factor.
No. A US gallon equals 3.785 liters, while an Imperial gallon is 4.546 liters. Always check which gallon type your measurement uses.
Primarily the United States, Liberia, and Myanmar. Some Caribbean nations use gallons alongside metric units.
The name comes from 'litron,' an old French unit. It was redefined in 1795 as 1 cubic decimeter during the French Revolution's metric system development.