Fuel prices and tank sizes
Comparing a US pump price per gallon against a European price per litre requires this conversion before any currency conversion. A 15-gallon tank holds 56.8 litres; the same car sold in Europe lists the capacity as 57 L.
Volume
Convert gallons to liters
1 us gallon equals 3.7854118 liters. Enter a value below to convert instantly.
US gallons to litres converts American fuel volumes, container sizes and recipe quantities into the unit used by the rest of the world's pumps and labels. Multiply by 3.785411784 — an exact figure, since the US gallon is defined as 231 cubic inches and the inch is defined in metres.
1 gal (US)
3.7854118 L
Multiply the number of us gallons by 3.785411784 to get liters. How this is calculated
Need the other direction? Convert liter to us gallon →
Formula
Multiply the number of us gallons by 3.785411784 to get liters.
Step by step
- Start with 1 gal (US).
- Multiply by the conversion factor 3.785411784.
- 1 × 3.785411784 = 3.7854118 L.
US Gallons to Liters conversion table
| US Gallons (gal (US)) | Liters (L) |
|---|---|
| 1 | 3.7854118 |
| 2 | 7.5708236 |
| 3 | 11.356235 |
| 5 | 18.927059 |
| 10 | 37.854118 |
| 20 | 75.708236 |
| 50 | 189.27059 |
| 100 | 378.54118 |
| 500 | 1,892.7059 |
| 1,000 | 3,785.4118 |
Where us gallons and liters are used together
Aquariums and water tanks
Tank volumes are quoted in gallons in the US and litres elsewhere, and dosing for water treatment is per unit volume. A 55-gallon tank is 208 L — get the conversion wrong and the dose is out by whatever factor you missed.
Beverage and container sizes
A US gallon of milk is 3.79 L, while the nearest metric container is usually a round 4 L. They are close enough to look interchangeable on a shelf and different enough to matter in a recipe scaled from one to the other.
Paint and coating coverage
Coverage is quoted in square feet per gallon or square metres per litre. Converting both the area and the volume — not just one of them — is what makes the two figures comparable.
Everyday us gallons worth knowing
Values people actually look up, with the reason each one comes up. Every figure is calculated with the same engine as the converter above.
| US Gallon (gal (US)) | Liter (L) | What it is |
|---|---|---|
| 1 | 3.7854118 | The base conversion |
| 2 | 7.5708236 | A large beverage container |
| 5 | 18.927059 | A US fuel can |
| 10 | 37.854118 | A round figure |
| 15 | 56.781177 | A typical car fuel tank |
| 20 | 75.708236 | A large fuel tank |
| 55 | 208.19765 | A standard drum, and a common aquarium size |
| 100 | 378.54118 | A round figure |
How these two units are defined
A litre is one cubic decimetre — exactly 0.001 m³. The US liquid gallon is defined as 231 cubic inches, which works out to exactly 3.785411784 L. The Imperial gallon, redefined in 1985 as exactly 4.54609 L, is a different unit that shares the name. Both split into four quarts and eight pints, but a US pint is 473 mL against an Imperial pint's 568 mL, so the whole family of subdivisions differs too.
Rounding and precision
The factor is exact, so precision follows the input. Fuel volumes are measured to about 0.01 gallon at the pump, so two decimals is the practical ceiling. Where a figure will be compared against a legal limit — a container capacity, a shipping restriction on flammable liquids — check which gallon the limit is written in before converting, because the 20% US–Imperial gap is far larger than any rounding you might worry about.
Mistakes people make with this conversion
-
Using the wrong gallon
A US gallon is 3.785 L and an Imperial gallon is 4.546 L. Applying the US factor to a UK figure understates the volume by about 17%, which is the single largest error available in this conversion.
-
Mixing US and Imperial subdivisions
A US pint is 16 US fluid ounces (473 mL); an Imperial pint is 20 Imperial fluid ounces (568 mL). Even the fluid ounces differ — 29.57 mL against 28.41 mL.
-
Converting dry volumes with a liquid factor
The US dry gallon is a separate unit of about 4.405 L, used for produce. It is rare, but it does appear in agricultural figures.
Read more about these units
Sources for this page
- Special Publication 811 — Guide for the Use of the International System of Units (SI)
- Publications and Documentary Standards (NIST Handbook 44, Handbook 133)
Content on this page last reviewed 12 August 2026. Spotted an error? Report it — see also how these values are calculated.
Convert US Gallon to other volume units
1 gal (US) expressed in every other volume unit on this site.
- Liter L 3.7854118
- Milliliter mL 3,785.4118
- Centiliter cL 378.54118
- Deciliter dL 37.854118
- Dekaliter daL 0.37854118
- Hectoliter hL 0.037854118
- Kiloliter kL 0.0037854118
- Microliter µL 3,785,411.8
- Nanoliter nL 3,785,411,800
- Picoliter pL 3,785,411,800,000
- Femtoliter fL 3.7854118e+15
- Attoliter aL 3.7854118e+18
- Megaliter ML 0.0000037854118
- Gigaliter GL 3.7854118e-9
- Petaliter PL 3.7854118e-15
- Exaliter EL 3.7854118e-18
- Dekastere dast 0.00037854118
- Metric Cup cup (metric) 15.141647
- Metric Tablespoon tbsp (metric) 252.36079
- Metric Teaspoon tsp (metric) 757.08236
- Cubic Meter m³ 0.0037854118
- Cubic Kilometer km³ 3.7854118e-12
- Cubic Centimeter cm³ 3,785.4118
- Cubic Millimeter mm³ 3,785,411.8
- Drop gtt 75,708.236
- Cubic Mile mi³ 9.0816858e-10
- Cubic Yard yd³ 0.0049511317
- Cubic Foot ft³ 0.13368056
- Cubic Inch in³ 231
- Hundred Cubic Feet ccf 0.0013368056
- Ton Register RT 0.0013368056
- Acre-foot ac·ft 0.0000030688833
- Acre-inch ac·in 0.000036826599
- Cord cord 0.0010443793
- Cord Foot cord ft 0.0083550347
- Board Foot bf 1.6041667
- US Gallon gal (US) 1
- US Quart qt (US) 4
- US Pint pt (US) 8
- US Cup cup (US) 16
- US Gill gi (US) 32
- US Fluid Ounce fl oz (US) 128
- US Tablespoon tbsp (US) 256
- US Teaspoon tsp (US) 768
- US Dessertspoon dstspn (US) 384
- US Fluid Dram fl dr (US) 1,024
- US Minim min (US) 61,440
- US Barrel (oil) bbl (oil) 0.023809524
- US Barrel (liquid) bbl (liq) 0.031746032
- US Barrel (federal, beer) bbl (beer) 0.032258065
- US Hogshead hhd (US) 0.015873016
- Tun tun 0.003968254
- US Bushel bu (US) 0.10742088
- US Peck pk (US) 0.4296835
- US Dry Gallon gal (US dry) 0.85936701
- US Dry Quart qt (US dry) 3.437468
- US Dry Pint pt (US dry) 6.8749361
- US Barrel (dry) bbl (dry) 0.032738095
- Imperial Gallon gal (UK) 0.83267418
- Imperial Quart qt (UK) 3.3306967
- Imperial Pint pt (UK) 6.6613935
- Imperial Cup cup (UK) 13.322787
- Imperial Gill gi (UK) 26.645574
- Imperial Fluid Ounce fl oz (UK) 133.22787
- Imperial Tablespoon tbsp (UK) 213.16459
- Imperial Teaspoon tsp (UK) 639.49377
- Imperial Fluid Dram fl dr (UK) 1,065.823
- Imperial Minim min (UK) 63,949.377
- Imperial Bushel bu (UK) 0.10408427
- Imperial Peck pk (UK) 0.41633709
- Imperial Dessertspoon dstspn (UK) 319.74689
- Imperial Barrel bbl (UK) 0.023129838
- Acre-foot (US survey) ac·ft (US) 0.0000030688649
- Cor (Biblical) cor 0.017206417
- Homer (Biblical) homer 0.017206417
- Bath (Biblical) bath 0.17206417
- Hin (Biblical) hin 1.032385
- Cab (Biblical) cab 3.0971551
- Log (Biblical) log 12.38862
- Doe 되 2.0984519
- Hop 홉 20.984519
- Jak 작 209.84519
- Mal 말 0.20984519
- Seom 섬 0.020984519
- Earth's Volume V⊕ 3.4953017e-24
About the us gallon
The us gallon (gal (US)) is a US unit of volume.
About the liter
The liter (L) is a Metric unit of volume.
Related conversions
Frequently asked questions
How many litres in a US gallon?
Exactly 3.785411784 L. The gallon is defined as 231 cubic inches, and since the inch is exactly 2.54 cm the conversion is exact rather than measured.
How many litres is a 55-gallon drum?
55 US gallons is 208.2 L. The nearest metric standard drum is 200 L, so the two are not interchangeable for capacity planning.
Why is a US gallon smaller than an Imperial one?
The US kept the older English wine gallon of 231 cubic inches, while Britain redefined its gallon in 1824 based on the volume of ten pounds of water. The two have been separate units ever since.
How many liters are in a us gallon?
One us gallon equals 3.7854118 liters.
How do you convert us gallons to liters?
Multiply the number of us gallons by 3.785411784 to get liters.
What is 1 liter in us gallons?
One liter equals 0.26417205 us gallons.
When would I convert us gallons to liters?
This conversion is common when cooking recipes, fuel, beverages, and container capacity.