1. How to convert imperial gallons to liters
The conversion is a single multiplication: L = imp gal × 4.54609. Both units are defined
against the same base — the litre (L) — so the factor is fixed and the result
is exact to the precision shown.
Worked at the two values people ask for most: 1 imp gal = 4.54609 L and
5 imp gal = 22.73045 L. Going the other way, imp gal = L × 0.219969248299, so
1 L = 0.21996925 imp gal.
Results are given to eight significant figures. That is more precision than most jobs need — for a rough figure, treat 1 imp gal as about 4.54609 L and adjust — but rounding early and multiplying afterwards is how a small error becomes a visible one, so the full figure is what the converter carries.
2. Gallons to Litres conversion table
| Gallons (imperial) (imp gal) | Litres (L) |
|---|---|
| 1 imp gal | 4.54609 L |
| 2 imp gal | 9.09218 L |
| 3 imp gal | 13.63827 L |
| 5 imp gal | 22.73045 L |
| 10 imp gal | 45.4609 L |
| 15 imp gal | 68.19135 L |
| 20 imp gal | 90.9218 L |
| 50 imp gal | 227.3045 L |
| 100 imp gal | 454.609 L |
Every row is the same factor applied — nothing in the table is a special case, and any value in between behaves the same way. Type your own figure into the converter above and the Formula tile shows the arithmetic being used, so the result is checkable rather than taken on trust.
3. What the two units are
- Gallons (imperial) (imp gal). One imp gal is 4.54609 L.
- Litres (L). One L is 1 L.
Both are converted through the litre (L): the value is multiplied by its own unit's factor to reach the base, then divided by the target unit's factor to leave it. No direct imperial gallons to liters factor has to exist or be kept correct, which is also why the converter can show the same value in all 14 volume & capacity units at once.
US and imperial capacity units share names but not sizes. A US gallon is exactly 3.785411784 L and an imperial gallon exactly 4.54609 L — 20% larger — while the imperial fluid ounce is the smaller ounce, because an imperial gallon is 160 fluid ounces where a US gallon is 128. Every unit here is labelled US or imperial for that reason.
If the pair you actually want is not this one, the full unit converter runs every 14 volume & capacity units off the same factor table, along with 11 other categories of measurement.
4. Gallons to Litres FAQs
How do I convert imperial gallons to liters?
Multiply by 4.54609. 1 imp gal = 4.54609 L, and 5 imp gal = 22.73045 L. The factor is exact to the precision shown, so the only rounding is the one you choose to do at the end.
How many liters is 1 imp gal?
1 imp gal = 4.54609 L. The full formula is L = imp gal × 4.54609, and 1 L = 0.21996925 imp gal going the other way.
What is 5 imp gal in L?
5 imp gal = 22.73045 L. The table above works the same factor through 9 values, and the converter takes any figure you type — including decimals.
How do I convert L to imp gal?
imp gal = L × 0.219969248299, so 1 L = 0.21996925 imp gal. Use the Swap button in the converter to reverse the direction without retyping the value.
US or imperial?
Both are in the converter and every unit is labelled. A US gallon is exactly 3.785411784 L and an imperial gallon exactly 4.54609 L, a 20% difference; the imperial fluid ounce is the smaller of the two ounces, because an imperial gallon holds 160 of them against a US gallon’s 128.
Is anything I type sent to a server?
No. The factor table ships with the page and every conversion runs in your browser. Nothing is uploaded, logged or written to storage, and the converter keeps working offline once the page has loaded.