2-Stroke Oil Mix Ratio Charts
Printable reference charts for every common 2-stroke mix ratio, in both US (gallons → ounces) and metric (litres → millilitres). Bookmark or print this page for the shed.
100:1 ratio
| Gallons of gas | oz of oil |
|---|---|
| 0.5 | 0.64 |
| 1 | 1.28 |
| 1.5 | 1.92 |
| 2 | 2.56 |
| 2.5 | 3.2 |
| 3 | 3.84 |
| 4 | 5.12 |
| 5 | 6.4 |
| 6 | 7.68 |
| Litres of gas | ml of oil |
|---|---|
| 1 | 10 |
| 2 | 20 |
| 3 | 30 |
| 4 | 40 |
| 5 | 50 |
| 10 | 100 |
| 15 | 150 |
| 20 | 200 |
| 25 | 250 |
50:1 ratio
| Gallons of gas | oz of oil |
|---|---|
| 0.5 | 1.28 |
| 1 | 2.56 |
| 1.5 | 3.84 |
| 2 | 5.12 |
| 2.5 | 6.4 |
| 3 | 7.68 |
| 4 | 10.24 |
| 5 | 12.8 |
| 6 | 15.36 |
| Litres of gas | ml of oil |
|---|---|
| 1 | 20 |
| 2 | 40 |
| 3 | 60 |
| 4 | 80 |
| 5 | 100 |
| 10 | 200 |
| 15 | 300 |
| 20 | 400 |
| 25 | 500 |
40:1 ratio
| Gallons of gas | oz of oil |
|---|---|
| 0.5 | 1.6 |
| 1 | 3.2 |
| 1.5 | 4.8 |
| 2 | 6.4 |
| 2.5 | 8 |
| 3 | 9.6 |
| 4 | 12.8 |
| 5 | 16 |
| 6 | 19.2 |
| Litres of gas | ml of oil |
|---|---|
| 1 | 25 |
| 2 | 50 |
| 3 | 75 |
| 4 | 100 |
| 5 | 125 |
| 10 | 250 |
| 15 | 375 |
| 20 | 500 |
| 25 | 625 |
32:1 ratio
| Gallons of gas | oz of oil |
|---|---|
| 0.5 | 2 |
| 1 | 4 |
| 1.5 | 6 |
| 2 | 8 |
| 2.5 | 10 |
| 3 | 12 |
| 4 | 16 |
| 5 | 20 |
| 6 | 24 |
| Litres of gas | ml of oil |
|---|---|
| 1 | 31.25 |
| 2 | 62.5 |
| 3 | 93.75 |
| 4 | 125 |
| 5 | 156.25 |
| 10 | 312.5 |
| 15 | 468.75 |
| 20 | 625 |
| 25 | 781.25 |
25:1 ratio
| Gallons of gas | oz of oil |
|---|---|
| 0.5 | 2.56 |
| 1 | 5.12 |
| 1.5 | 7.68 |
| 2 | 10.24 |
| 2.5 | 12.8 |
| 3 | 15.36 |
| 4 | 20.48 |
| 5 | 25.6 |
| 6 | 30.72 |
| Litres of gas | ml of oil |
|---|---|
| 1 | 40 |
| 2 | 80 |
| 3 | 120 |
| 4 | 160 |
| 5 | 200 |
| 10 | 400 |
| 15 | 600 |
| 20 | 800 |
| 25 | 1,000 |
20:1 ratio
| Gallons of gas | oz of oil |
|---|---|
| 0.5 | 3.2 |
| 1 | 6.4 |
| 1.5 | 9.6 |
| 2 | 12.8 |
| 2.5 | 16 |
| 3 | 19.2 |
| 4 | 25.6 |
| 5 | 32 |
| 6 | 38.4 |
| Litres of gas | ml of oil |
|---|---|
| 1 | 50 |
| 2 | 100 |
| 3 | 150 |
| 4 | 200 |
| 5 | 250 |
| 10 | 500 |
| 15 | 750 |
| 20 | 1,000 |
| 25 | 1,250 |
How to read these charts
Each block covers one mix ratio and holds two tables: the US table, which converts gallons of gas to fluid ounces of oil, and the metric table, which converts litres to millilitres. Find the row for the amount of gas you are mixing and add the amount of oil in the column beside it.
Every figure comes from the same division the calculator uses: oil = fuel ÷ ratio. That is why 32:1 shows as 4 oz per gallon and 31.25 ml per litre, and why no chart here can disagree with the calculator or with the guides.
What each ratio is for
- 50:1: nearly all modern handheld equipment and most current premix outboards.
- 40:1: equipment from the 1970s through the 1990s, budget tools sold today, and many dirt bikes.
- 32:1: vintage chainsaws, older Lawn-Boy mowers, and many break-in schedules after a cylinder rebuild.
- 25:1: older outboards and period equipment that call for the richest common mix.
- 100:1: only with oils explicitly rated for that ratio.
- 20:1: vintage engines and some hard-revving race applications.
Printing them for the shed
The print button above produces a clean version with the navigation, header and ads stripped out, sized to pin above a workbench or fold into a toolbox. It is the fastest way to get the ratio right when your hands are dirty and your phone is in your pocket.
A practical tip: pencil onto the printed copy which of your own machines uses which ratio. The chart is generic; your shed is not.
Common mistakes when using a chart
US and imperial gallons are not the same thing. These charts use the US gallon of 128 fluid ounces, so 50:1 is 2.56 oz. The figure would be different against an imperial gallon.
The other classic error is trusting the bottle's dosing instead of the chart. The 2.6 oz single-use bottles are sized for one gallon at 50:1, so the moment your machine calls for 40:1, or your can holds two gallons, that bottle no longer matches.