Cocoa percentage blender
Works out how much of two chocolates to combine for a target cocoa percentage, or how much cocoa butter, cocoa mass or sugar to add to chocolate you already have.
500g of the 85% and 500g of the 55%
That makes 1000g at 70% cocoa. The 85% chocolate is 50% of the blend by weight.
What this cannot tell you
- Cocoa percentage counts cocoa butter and non-fat cocoa solids together. Two blends at the same percentage can differ in fat content, and so in fluidity, snap and intensity. The tool reports the percentage and nothing about the split.
- It does not track milk solids, sugar type or emulsifier. Blending a dark chocolate with a milk chocolate gives a chocolate with some milk in it, whatever the cocoa percentage says.
- It cannot tell you what the result may legally be called. Names such as dark, milk and couverture are set by composition rules that vary by country and depend on more than total cocoa.
- The percentage printed on a bar is a declared minimum, often rounded. A blend of two labelled chocolates is only as exact as the labels.
- Stirring an ingredient into finished chocolate is not the same as formulating with it. Sugar added after refining stays gritty, and any addition changes how the chocolate tempers.
How the sum works
Cocoa percentage is a share of weight, and weight is conserved when two things are mixed. So a blend’s percentage is a weighted average, and the share of the first chocolate needed is the distance from the second to the target, divided by the distance between the two.
For an 85% and a 55% blended to 70%: (70 − 55) ÷ (85 − 55) = 0.5, so half of each. To reach 75% it is (75 − 55) ÷ 30, two-thirds of the 85%. A target outside the two can never be reached, in any proportion.
Why the same percentage can behave differently
Cocoa percentage counts cocoa butter and the non-fat cocoa solids together. Two chocolates at 70% can hold quite different amounts of each, and it is the butter that decides how fluid the chocolate is and the solids that carry most of the flavour. Raising a percentage with cocoa butter and raising it with cocoa mass arrive at the same number and a different chocolate. See what cocoa butter does and what the percentage means.