How do I calculate the gas-to-oil ratio?

Enter the fuel volume and oil volume in the same unit (e.g., gallons, liters). The calculator divides fuel by oil to give the ratio (e.g., 50:1) and also shows the percentage of each component in the mixture.

What does a 50:1 ratio mean?

A 50:1 ratio means 50 parts fuel to 1 part oil by volume. For example, 50 gallons of fuel mixed with 1 gallon of oil. The calculator computes this from your entered volumes.

Can I use different units for fuel and oil?

No, both volumes must be in the same unit. If you have measurements in different units, convert them first (e.g., liters to milliliters) before entering.

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Gas–Oil Ratio Calculator.

Calculate measured fuel-to-oil composition from two volumes; no manufacturer mixture ratio is assumed.

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Set your values

Results update as you type.

02 / ANSWER

Fuel volume

Oil volume

Results update automatically as you type.

How to Use

Scenario arithmetic only. Enter every material factor; no live, regional, manufacturer, or safety data is used.

FAQs

What assumptions are used?

Every material measurement and scenario factor is entered explicitly; the calculator does not fetch live or regional data.

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Cite this calculator

Canonical URL: https://mathify.one/en/everyday-life/gas-oil-ratio

Cite as: Mathify. (n.d.). Gas–Oil Ratio Calculator. https://mathify.one/en/everyday-life/gas-oil-ratio

Use Cases

Mixing fuel for two-stroke engines

Determine the exact ratio and composition when mixing gasoline and oil for chainsaws, leaf blowers, or outboard motors, without relying on a preset ratio.

Example: Enter 5 liters of fuel and 100 ml of oil to see the ratio and percentages.

Checking a pre-mixed fuel sample

Verify the ratio of an already mixed fuel-and-oil sample to ensure it matches the manufacturer's recommendation.

Example: Enter 1 gallon of fuel and 2.6 ounces of oil to check if it's 50:1.

Frequently Asked Questions

How do I calculate the gas-to-oil ratio?: Enter the fuel volume and oil volume in the same unit (e.g., gallons, liters). The calculator divides fuel by oil to give the ratio (e.g., 50:1) and also shows the percentage of each component in the mixture.
What does a 50:1 ratio mean?: A 50:1 ratio means 50 parts fuel to 1 part oil by volume. For example, 50 gallons of fuel mixed with 1 gallon of oil. The calculator computes this from your entered volumes.
Can I use different units for fuel and oil?: No, both volumes must be in the same unit. If you have measurements in different units, convert them first (e.g., liters to milliliters) before entering.

Tips & Common Mistakes

Tips

Always use the same unit for both fuel and oil volumes to get an accurate ratio.
For small quantities, convert to milliliters or ounces to avoid decimal errors.
Double-check your oil volume: a small mistake can significantly change the ratio.
Use the composition percentages to understand the mixture's oil content by volume.

Common Mistakes to Avoid

Entering fuel and oil in different units (e.g., gallons and liters) without converting.
Mixing up the order: the ratio is fuel divided by oil, not oil divided by fuel.
Assuming a standard ratio like 50:1; this calculator does not assume any ratio—you must enter your own volumes.

Last updated: August 13, 2026