Out of buttermilk
Buttermilk from milk and cream of tartar, or milk and lemon juice
Both charts give two ways to make a buttermilk stand-in from ordinary milk: stir in cream of tartar, or add lemon juice or vinegar.
For cream of tartar they do not print the same amount. Colorado State gives a range and Mississippi State gives a single amount at the top of it, so both are shown. For lemon juice or vinegar the two charts match, and that card shows one figure.
Sources disagree · replaces 1 cup buttermilk
Regular (sweet) milk + cream of tartar
The charts below do not print the same thing for 1 cup of buttermilk. We show each one as printed instead of averaging them.
Colorado State Extension — a range
| Amount | Ingredient | ≈ grams |
|---|---|---|
| 1 cup | regular (sweet) milk | |
| 1¼–1¾ tsp | cream of tartar | 3.8–5.3 g |
- Colorado State University Extension, Ingredient Substitutions (web page) — checked 2026-09-27
Mississippi State Extension — a single amount
| Amount | Ingredient | ≈ grams |
|---|---|---|
| 1 cup | regular (sweet) milk | |
| 1¾ tsp | cream of tartar | 5.3 g |
- Mississippi State University Extension, Ingredient Substitutions and Equivalents (Publication 1690, 2024), p. 5 — checked 2026-09-27
Grams are volume-to-weight estimates from USDA FoodData Central (SR Legacy): Leavening agents, cream of tartar — 1 tsp = 3 g. Blank means the chart does not say which kind to use, or the unit is not a volume.
Replaces 1 cup buttermilk
Regular (sweet) milk + lemon juice or vinegar
| Amount | Ingredient | ≈ grams |
|---|---|---|
| 1 cup minus 1 tbsp | regular (sweet) milk | |
| 1 tbsp | lemon juice or vinegar |
- Colorado State University Extension, Ingredient Substitutions (web page) — checked 2026-09-27
- Mississippi State University Extension, Ingredient Substitutions and Equivalents (Publication 1690, 2024), p. 5 — checked 2026-09-27
✓ 2 sources match Colorado State Extension, Mississippi State Extension list the same amounts.
Before you swap
- Let the lemon juice or vinegar version stand before you use it. Colorado State says 5 minutes; Mississippi State says 20 minutes at room temperature.
- Both charts also list plain yogurt as a stand-in for buttermilk. That swap is not on this page yet.
How these ratios are checked: our method. Spotted a mismatch with a chart? Tell us and we will recheck the original.