mL to Gallons Converter
Enter milliliters or gallons. US liquid is the default; a pasted unit sets direction, and an explicit US, Imperial, or UK gallon label also sets the system.
US liquid gallon is the default. Choose Imperial only when that is the definition you need.
Paste mL or a gallon label. Explicit US, Imperial, or UK text overrides the menu; bare gal uses the selected system.
How to convert mL to US liquid gallons
US liquid gallons = milliliters ÷ 3,785.411784. For example, 1,000 mL is approximately 0.264172052 US liquid gallons.
How to convert mL to Imperial gallons
Imperial gallons = milliliters ÷ 4,546.09. For example, 1,000 mL is approximately 0.219969248 Imperial gallons.
Common mL to gallon values
| Milliliters | US liquid gallons | Imperial gallons |
|---|---|---|
| 100 mL | ≈ 0.026417205 gal | ≈ 0.021996925 gal |
| 500 mL | ≈ 0.132086026 gal | ≈ 0.109984624 gal |
| 1,000 mL | ≈ 0.264172052 gal | ≈ 0.219969248 gal |
| 3,785.411784 mL | 1 gal | ≈ 0.832674185 gal |
| 4,546.09 mL | ≈ 1.200949926 gal | 1 gal |
How to convert gallons back to milliliters
Milliliters = gallons × the selected gallon factor. Half a US liquid gallon is 1,892.705892 mL; half an Imperial gallon is 2,273.045 mL.
Why the two gallon factors differ
The US liquid gallon is defined as 231 cubic inches. With the international inch defined as exactly 25.4 mm, that equals exactly 3,785.411784 mL. NIST SP 811 also provides a supporting conversion table, but its displayed gallon-to-liter value is rounded.
UK law defines the Imperial gallon as exactly 4.54609 liters, or 4,546.09 mL. Because the units are different, always keep the selected system with the number you copy or share.
Pasted labels, fractions, and scope
You can paste mL, milliliter, millilitre, US gal, US liquid gallon, Imperial gallon, or UK gal. An mL label sets the direction. An explicit US, US liquid, Imperial, or UK gallon label sets both direction and system. A bare gal, gallon, or liquid gallon label follows the chosen system. Decimals, scientific notation, and fractions such as 1/2 are accepted.
This page intentionally excludes US dry gallons, liters, fluid ounces, weights, ingredients, container dimensions, and fuel economy. It uses immediate visual feedback, so animation or sound would add distraction rather than clarity.
Frequently asked questions
How many mL are in a US gallon?
One US liquid gallon is exactly 3,785.411784 milliliters. This tool does not use the US dry gallon.
How many mL are in an Imperial gallon?
One Imperial gallon is exactly 4,546.09 milliliters under UK law.
What is the formula for mL to gallons?
For US liquid gallons, divide mL by 3,785.411784. For Imperial gallons, divide mL by 4,546.09.
How do I convert gallons back to mL?
Multiply US liquid gallons by 3,785.411784 or Imperial gallons by 4,546.09. Swap preserves the selected gallon system and carries the unrounded value.
Which gallon does a value labeled only gal use?
A plain gal or gallon label follows the system selector. An explicit US, US liquid, Imperial, or UK label overrides the selector.
Does this convert liters, dry gallons, or weight?
No. It converts milliliters with US liquid or Imperial gallons only. Liters, US dry gallons, fluid ounces, and weight or ingredient conversions are outside this page’s scope.
Why is the US factor more precise than some conversion tables?
The exact value follows from the US liquid gallon definition of 231 cubic inches and the exact international inch of 25.4 millimeters. Some reference tables print a rounded decimal for convenience.