Mix ratio

Two-stroke oil, coolant, cleaning agent or fertiliser: the ratio is on the container. Enter it and how much you need to mix, and you get the amounts.

The explanation is shown. Quick: ratio, percentage and dilution. Advanced: also three parts and two strengths — and the same mix in other quantities.

Your numbers

How is it written on the can?

Part A

Part B

Total amount you need

Part A

0.098l

Part B

4.902l

In millilitres

98 + 4,902ml

Per litre of finished mixture

19.6ml

1Parts in total: 1 + 50 = 511 : 50 is 51 parts in total — not 50. That is the typical mistake.
21 part = 5 l / 51 = 0.098 l
3A = 1 · 0.098 = 0.098 l · B = 50 · 0.098 = 4.902 l

a : b → a/(a+b) · quantity

1 : 50 means 1 part of one to 50 parts of the other — 51 parts in total.

a : b : c → a/(a+b+c) · quantity

The same rule with three parts: add all the parts together first.

C₁ · V₁ = C₂ · V₂

Dilution: the amount of substance is the same before and after — only water is added.

A : B = |C − B| : |A − C|

The cross rule: mix strengths A and B to strength C. Diluting with water is the cross rule with B = 0 %.

Always follow the manufacturer's instructions. The tool only calculates with the numbers you enter yourself.

In depth: more numbers and “what if”

The same mix in other quantities