Tools · dilution
Dilution ratio calculator.
Type your bottle size and the ratio on the label. The answer is how much concentrate goes in first, before the water.
Why there are two answers
A ratio written 1:10 is read two different ways by two different halves of this industry. Some brands mean one part concentrate added to ten parts water, which makes eleven parts in total. Others mean one part concentrate made up to ten parts of finished liquid, so nine parts water.
At 1:10 the gap is about ten per cent of your concentrate — annoying, not dangerous. At 1:4 it is twenty-five per cent, which is the difference between a wheel cleaner that works and one that etches. The label is the authority. If it gives a target quantity as well as a ratio — “4 oz per quart” — use that, because it removes the ambiguity entirely.
This calculator does not pick for you and does not average the two. Averaging would produce a number that neither manufacturer intended.
Common mixes
Concentrate needed, in fluid ounces, read as one part product to n parts water.
| Ratio | 16 oz | 22 oz | 24 oz | 32 oz |
|---|---|---|---|---|
| 1:4 | 3.2 | 4.4 | 4.8 | 6.4 |
| 1:10 | 1.45 | 2 | 2.18 | 2.91 |
| 1:15 | 1 | 1.38 | 1.5 | 2 |
| 1:20 | 0.76 | 1.05 | 1.14 | 1.52 |
| 1:32 | 0.48 | 0.67 | 0.73 | 0.97 |
| 1:128 | 0.12 | 0.17 | 0.19 | 0.25 |
Arithmetic, not a measurement — there is no source line on this table because there is nothing to source. Every figure is the bottle size divided by the ratio plus one.
Two things worth knowing before you mix
- Concentrate first, then water. Filling with water first and adding concentrate on top makes most detailing chemicals foam over the neck of the bottle, and you lose an unknown amount of what you just measured.
- Dilute with the water you will use. Hard water changes how some products behave, and a mix made with distilled water then topped up from the tap is not the mix you tested.