Why dough temperature matters
Fermentation speed depends strongly on temperature. A dough that starts a few degrees cooler than the recipe expected can take noticeably longer to rise, and a warmer one can overproof before you check it. Controlling the one ingredient you can easily warm or cool, the water, is the simplest way to start every bake from the same point, so the recipe's timings mean something.
Many sourdough recipes aim for a dough temperature somewhere around 75 to 80 °F (24 to 27 °C). Use whatever your recipe asks for.
The formula
This is the standard bakers' method. Multiply the target by the number of temperature factors, then subtract the ones you know:
With starter or levain: water = target × 4 − (room + flour + levain + friction)
Without: water = target × 3 − (room + flour + friction)
Worked example (°F). Target 78, room 72, flour 70, levain 75, hand mixed. Water = 78 × 4 − (72 + 70 + 75 + 0) = 312 − 217 = 95 °F.
In °C. Target 25, room 22, flour 21, levain 24. Water = 100 − 67 = 33 °C.
Use one unit throughout. Friction factors measured in °F and °C are different numbers.
Finding your mixer's friction factor
Mixing warms dough. By hand the effect is small; a stand mixer adds more, and how much depends on the machine, speed and time. Measure it once:
- Note the room, flour, levain and water temperatures and mix as usual.
- Take the dough's temperature right after mixing.
- Friction = final dough × 4 − (room + flour + levain + water). Use × 3 and leave out levain if there is none.
Example: the dough reads 80 °F after mixing with room 72, flour 70, levain 75 and water 95. Friction = 320 − 312 = 8 °F. Enter 8 next time.
Limits of this calculator
- It assumes a typical sourdough where water, flour and levain dominate. Large amounts of cold add-ins (butter, eggs, milk) shift the result.
- If the answer is very hot or near freezing, the calculator says so. Very hot water can stress a starter; change the room or ingredient temperatures instead, or adjust fermentation time.