Brew ratio and dilution are different steps
The brewing ratio compares grounds with water before extraction. The dilution ratio compares filtered concentrate with the liquid you add afterwards. A 1:8 brew ratio does not mean you should dilute your concentrate with eight parts water.
For example, Counter Culture publishes a recipe using 200 g coffee and 1,600 g water, then suggests a starting dilution of equal parts concentrate and cold water. That is one recipe, not a rule for every concentrate. The amount recovered after filtering will be less than the starting water.
How much water should I add?
Use the maker’s directions for a bought concentrate. For a homemade brew, start from the dilution in the recipe you followed and adjust a small serving to taste. Write down the ratio you prefer before scaling it to a pitcher.
In this tool, 1:2 means one part concentrate plus two parts added liquid. It makes three parts finished drink. Ratio labels are easy to misread when one recipe describes concentrate-to-water and another describes concentrate-to-total.
| Concentrate : added liquid | Add | Total, before ice |
|---|---|---|
| 2:1 | 50 ml | 150 ml |
| 1:1 | 100 ml | 200 ml |
| 1:2 | 200 ml | 300 ml |
| 1:3 | 300 ml | 400 ml |
Working backwards from a serving
For a 360 ml drink at 1:2, divide 360 by three: use 120 ml concentrate and 240 ml added liquid. For a batch serving four people, you can enter the combined volume, then portion the drink afterwards.
Milk and ice change the experience
The volume arithmetic works for water or milk, but those drinks will taste different. If you use both, the added-liquid result is their combined volume. For example, a 150 ml allowance could be 100 ml milk and 50 ml water.
Leave room for ice. The tool does not predict how much it melts, and it does not infer a concentrate’s strength from its brewing ratio. Two concentrates can need different dilution even when the same amount of coffee went into making them.
Sources & further reading
- Counter Culture: cold brew
One recipe using a 1:8 brew ratio and a suggested 1:1 serving dilution.
Research checked 11 October 2026. AI-assisted research and writing by Coffee Shops Editorial Desk. No firsthand tasting or independent human review is claimed.