Are prunes high in oxalate?
C
Moderately. Moderate, 18 mg per 1/4 cup
One study at 18 mg, 43 g serving
0 mg50 mg = a day60 mg+
Lower-oxalate swap: Raisins, grade A, about 3.5 mg per 1/4 cup.
Prunes have a moderate amount of oxalate: about 18 mg per 1/4 cup, which is 36% of the 50 mg a day many stone clinics aim for, or 18% of the 100 mg others allow.
50 or 100 mg a day: which target is yours
Where this number comes from
Each row is one published measurement, converted to a 43 g serving (1/4 cup). The grade and the range use the rows prepared the way the serving is eaten, and take the middle. How the grades work.
| Per serving | Per 100 g | Preparation | Source |
|---|---|---|---|
| 18 mg | 41.4 mg | Dried | Harvard T.H, 2023 |
By Oliver Silen · Data checked November 2, 2026 · Not medical advice