Single conversion
5 US gal converts to approximately 18.927059 L. This is the direct calculator result using the standard factor.
Common conversion calculator
Gallons to Litres Converter
Convert us gallons to litres with the exact formula, clear rounding notes and practical examples for everyday use.
On this page
How to convert us gallons to litres
input × 3.785411784
Use this converter for US vehicle, tank, jug and product specifications. The page explicitly uses US liquid gallons; UK imperial gallons require a different factor.
Imperial gallons are larger than US gallons. Do not mix them for fuel, tanks or recipe scaling.
Worked examples
Reverse check
If you convert 18.927059 L back, you get approximately 5 US gal. A tiny difference can appear because the displayed number is rounded.
Five US gallons is about 18.93 L. An answer around 22.7 L would indicate an imperial gallon.
Quick us gallons to litres reference values
The table applies the same us gallons to litres formula used by the calculator.
| Us Gallons | Litres |
|---|---|
| 1 | 3.7854 |
| 2 | 7.5708 |
| 5 | 18.927 |
| 10 | 37.854 |
| 20 | 75.708 |
| 50 | 189.27 |
| 100 | 378.54 |
Use the nearest row to test whether a litres result is in the right range. Do not copy a rounded table value when the original US gallons measurement is more precise or the decision is close to a practical threshold.
5-gallon tank: US or imperial?
A tank marked 5 US gal holds 18.9271 L (5 × 3.785411784). But 5 imperial gal equals 22.7305 L (5 × 4.54609). That is a difference of about 3.80 litres for the same printed number.
| Label on product | In litres |
|---|---|
| 1 US liquid gallon | 3.785411784 L |
| 1 imperial gallon | 4.54609 L |
| 5 US liquid gallons | 18.9271 L |
| 5 imperial gallons | 22.7305 L |
Check whether an imported fuel container, pump or product specification says US gal or imperial gal before converting. This calculator intentionally converts US liquid gallons only.
Rounding, accuracy and common mistakes
Round to a tenth of a litre for broad capacity comparisons. Keep hundredths when estimating repeated fills or a liquid cost, but do not imply more accuracy than the source capacity.
Multiply by 3.785411784 after confirming the source is a US liquid gallon.
Precision example: 5 US liquid gallons×3.785411784=18.92705892 L. Display 18.9 L for a broad capacity comparison.
Printable chart and related converters
The chart gives quick values for common gallon containers; use the calculator for a decimal gallon figure or a specific equipment capacity.
Area Volume Conversion Chart
Use this printable reference for common us gallons to litres values, then return to the calculator for a specific or decimal input.
Open printable chartGallons to Litres Converter FAQs
What is the formula for gallons to litres?
litres = US gallons × 3.785411784.
How should I round us gallons to litres?
Round to a tenth of a litre for broad capacity comparisons. Keep hundredths when estimating repeated fills or a liquid cost, but do not imply more accuracy than the source capacity.
What should I check before using the converted litres value?
For fuel, chemicals or regulated storage, check the product documentation, temperature assumptions and safe fill level in addition to the conversion.
When this conversion is useful
For an imported aquarium or water tank, convert the stated US-gallon capacity to litres before comparing it with Australian equipment specifications. For liquids sold by volume, use the same gallon system for the container and the price calculation. Rated tank capacity is not necessarily a safe fill level.
Converting from litres instead? Use the litres to US gallons converter. For kitchen quantities, start with the Australian and US volume measures guide.
Bottom line
Use this page for a transparent us gallons to litres calculation, keep the source and result together, and apply the original source’s accuracy and limits. For fuel, chemicals or regulated storage, check the product documentation, temperature assumptions and safe fill level in addition to the conversion.
Reviewed for calculator quality: This unit conversion calculator was checked for input clarity, formula notes, rounding behaviour, examples, related links and general-information limitations. See the methodology notes and editorial review profile.