100 to 1 Fuel Mix Calculator
Enter your fuel amount and pick 100:1 or another ratio. The tool gives oil to add in fluid ounces, milliliters, tablespoons, and teaspoons. It also prints a quick chart for common can sizes.
Inputs
Helpful conversions: 1 cup = 8 fl oz, 1 tbsp = 0.5 fl oz, 1 tsp = 0.1667 fl oz, 1 fl oz = 29.5735 mL.
Results
Oil to add, fluid ounces
Oil to add, milliliters
Kitchen measures
| Fuel amount | Oil, fl oz | Oil, mL |
|---|
Tip, add some fuel first, add all the oil, then top up with fuel to the final amount, and shake to mix. Follow your equipment manual for the correct ratio.
Frequently Asked Questions
How much oil do I add for 1 gallon at 100 to 1?
For one gallon of fuel at a 100 to 1 ratio you add 1.28 fluid ounces of oil. That equals about 38 milliliters, which is roughly 2.6 tablespoons or about 7.7 teaspoons.
How much oil do I add for 1 quart or 1 liter at 100 to 1?
or one quart of fuel you add 0.32 fluid ounces of oil, which is about 9.5 milliliters, close to two teaspoons. For one liter of fuel you add 10 milliliters of oil, which is about 0.34 fluid ounces, also close to two teaspoons.
How can I figure out the oil amount for any fuel volume?
Take your fuel amount and divide by the mix ratio to get the oil amount. In U.S. units multiply gallons by 128 to get fluid ounces, then divide by the ratio. In metric multiply liters by 1,000 to get milliliters, then divide by the ratio. For example, two gallons at 100 to 1 need 2.56 fluid ounces of oil, which is about 76 milliliters.
What is the best way to mix the fuel and oil?
Pour some fuel into the can first, add the full measured oil amount, then top up with fuel to the final volume. Close the can and shake to mix well. Always use a clean container with clear markings and follow your equipment manual.
Is a 100 to 1 ratio safe for every two-stroke engine?
No. Some modern tools and certain synthetic oils are designed for 100 to 1, but many engines call for 50 to 1 or 40 to 1. Running leaner oil than specified can reduce lubrication and lead to damage. Using slightly more oil than required usually causes extra smoke and deposits. The safe choice is to follow the engine manual and the oil label.
Can I round the oil amount or measure with kitchen tools?
Small rounding is acceptable for home equipment. If you round, it is safer to round up the oil slightly rather than down. Useful references are that one fluid ounce is 29.57 milliliters, one tablespoon is one half fluid ounce, one teaspoon is about one sixth fluid ounce, and one cup is eight fluid ounces.