2-Stroke Oil Mixing Calculator

Amount of Fuel (litres):

Mix Ratio (e.g., 50 for 50:1):

How to Use the 2-Stroke Oil Mixing Calculator

The 2-Stroke Oil Mixing Calculator is a digital tool that helps you accurately calculate the amount of 2-stroke engine oil needed to mix with gasoline at a specific ratio (e.g., 50:1), ensuring proper lubrication and engine performance.

Why You Need This Calculator

2-stroke engines rely on oil mixed with fuel for lubrication. Incorrect mixing can lead to:

Too much oil → smoky exhaust, poor performance
Too little oil → engine damage or seizure

Whether you're using a chainsaw, outboard motor, lawnmower, or dirt bike, this calculator saves time and prevents costly mistakes.

How to Use the Calculator

Just follow these simple steps to calculate your 2-stroke oil mix:

Step 1: Enter the Amount of Fuel

In the first box, enter how much fuel (petrol/gasoline) you plan to mix in litres.
Example: 5 litres

Step 2: Enter the Mix Ratio

In the second box, enter your required oil mix ratio. This is usually specified in your engine’s user manual.
Common ratios:

50:1 – Most modern 2-stroke engines
40:1 – Older engines or specific manufacturers
25:1 – High-performance or racing engines

Example: 50 for a 50:1 ratio

Step 3: Click "Calculate Oil Needed"

After clicking the button, you'll instantly see:

Total fuel entered
Exact amount of oil needed in millilitres (ml)

Example Calculation

Fuel: 5 litres
Ratio: 50:1

Result:

Oil Required: 100 ml (5 litres ÷ 50 × 1000)

Why Accurate Mixing Matters

Improper mixing can result in:

Under-lubrication → increased engine wear, overheating
Over-lubrication → clogged spark plugs, excess smoke, and carbon deposits

A tool like this helps ensure fuel efficiency, engine longevity, and better performance.

Tips for Measuring

Use a graduated oil bottle or mixing cup for precise measuring
Always shake the fuel-oil mix thoroughly before using
Label containers to avoid confusion
Mix only what you’ll use in a few weeks—pre-mixed fuel can degrade over time

FAQ – 2-Stroke Oil Mixing Calculator

What is a 2-stroke oil mix ratio?

It's the proportion of fuel to oil. A 50:1 ratio means 50 parts fuel to 1 part oil. You mix 1 litre of oil for every 50 litres of fuel.

Can I use this calculator for gallons instead of litres?

The current version uses litres. If you need a gallon-based calculator, I can make a US version using the imperial system.

What happens if I get the mix wrong?

Too much oil: smoke, oily residue, fouled spark plugs
Too little oil: overheating, scoring of cylinder walls, engine seizure

Is this calculator accurate for all 2-stroke engines?

Yes, as long as you know the correct ratio recommended by your engine’s manual, it will give you accurate oil volume for that ratio.

Can I pre-mix fuel in advance?

Yes, but it’s best to use it within 30 days, or add a fuel stabilizer to prolong shelf life.