🥛 Yogurt Fermentation Time Calculator
Select your incubation temperature and desired tanginess level to see a typical fermentation time range for homemade yogurt.
How the hours are set
Two dropdowns, added together. The temperature sets a base incubation time, the tanginess adds to it, and the answer is shown as that figure through two hours later:
base hours: 100°F = 8, 110°F = 6, 115°F = 5
tanginess: mild +0, medium +2, tangy +5
shown = base + adjust, to + 2 hours| Temperature | Mild | Medium | Tangy |
|---|---|---|---|
| ~100 °F | 8-10 hrs | 10-12 hrs | 13-15 hrs |
| ~110 °F | 6-8 hrs | 8-10 hrs | 11-13 hrs |
| ~115 °F | 5-7 hrs | 7-9 hrs | 10-12 hrs |
The defaults, 110 °F and medium, give 8-10 hours — the overnight batch most people make. Tang comes from lactic acid, and acid keeps accumulating the longer the culture works, which is why tangy costs five extra hours at every temperature while a warmer incubation shortens all three columns.
Before the timer starts
- Heat the milk to 180-185 °F and hold it 10-20 minutes. That changes the whey proteins and is what makes set yogurt thick rather than drinkable. Skipping it is the usual reason for a runny batch.
- Cool to the incubation temperature before adding culture. Above roughly 120 °F the bacteria are killed outright; use 2 tablespoons of live plain yogurt per quart of milk.
- Leave the jar still. Moving or stirring mid-incubation breaks the curd as it forms and it will not knit back together.
Frequently asked questions
How long should yogurt incubate at 110 °F?
8 to 10 hours for a medium tang, 6 to 8 for mild and 11 to 13 for properly tart. Set it going in the evening and it is ready at breakfast.
How do I make yogurt more tangy?
Leave it longer. Five extra hours takes a 110 °F batch from 6-8 hours to 11-13, and the same shift applies at 100 and 115 °F. Straining afterwards concentrates the flavour further.
Why is my homemade yogurt runny?
Most often the milk was never held at 180 °F, the incubator ran cool, or the starter was old. Ultra-pasteurised milk and low-fat milk also set softer; a few spoons of milk powder thicken them.