Substitute for Buttermilk
Out of buttermilk mid-recipe? Here is the exact swap, measured — not "about a cup of something similar" — plus every alternative that genuinely works.
For 1 cup of buttermilk
1 cup milk + 1 tbsp lemon juice or white vinegar
Stir and rest 5 minutes until slightly curdled.
Data & method: Ratios follow standard US test-kitchen practice (King Arthur Baking's ingredient guides are the primary cross-check). Every number is checked by an automated test against its source. How we calculate →
Every option, in preference order
Best swap Milk + lemon juice or white vinegar
1 cup milk + 1 tbsp lemon juice or white vinegar
Stir and rest 5 minutes until slightly curdled.
Also works Thinned plain yogurt
¾ cup plain yogurt + ¼ cup milk
Scaled to what your recipe calls for
Milk + lemon juice or white vinegar, computed for the amounts recipes actually use:
| Recipe needs | Use instead |
|---|---|
| ¼ cup of buttermilk | ¼ cup milk + ¾ tsp lemon juice or white vinegar |
| ½ cup of buttermilk | ½ cup milk + 1½ tsp lemon juice or white vinegar |
| ¾ cup of buttermilk | ¾ cup milk + 2¼ tsp lemon juice or white vinegar |
| 1 cup of buttermilk | 1 cup milk + 1 tbsp lemon juice or white vinegar |
| 1½ cup of buttermilk | 1½ cups milk + 1½ tbsp lemon juice or white vinegar |
| 2 cup of buttermilk | 2 cups milk + 2 tbsp lemon juice or white vinegar |
Need a different amount — or a different ingredient?
The calculator scales every option to your exact amount, for all 17 staples we cover.
Best swap Milk + lemon juice or white vinegar
1 cup milk + 1 tbsp lemon juice or white vinegar
Stir and rest 5 minutes until slightly curdled.
Also works Thinned plain yogurt
¾ cup plain yogurt + ¼ cup milk
Other swaps bakers look for
Frequently Asked Questions
What can I use instead of buttermilk?
The best swap for 1 cup of buttermilk is 1 cup milk + 1 tbsp lemon juice or white vinegar — stir and rest 5 minutes until slightly curdled. 1 more measured option below.
Which buttermilk substitute works best?
Milk + lemon juice or white vinegar is the closest match in most baking. Thinned plain yogurt also works.
How much substitute do I use for a different amount of buttermilk?
Scale the parts linearly. The table on this page covers the common amounts, and the calculator scales every option to exactly what your recipe calls for — never a vague "adjust to taste".