Free tool
Cambridge PUM / UMS calculator
Convert a raw mark into a Percentage Uniform Mark on the 0–100 scale. Enter your mark, the total, and the A–E thresholds for your session — get your PUM, your grade, and the marks to the next grade.
Enter the A–E raw-mark thresholds from your official Cambridge grade threshold table for that component. The PUM scale fixes A=80, B=70, C=60, D=50, E=40.
Enter your mark, the total, and at least one boundary to see your PUM.
How the uniform mark scale works
A raw mark on its own doesn't mean the same thing from session to session, because papers vary in difficulty. The uniform mark scale fixes each grade boundary to a set value — A=80, B=70, C=60, D=50, E=40 — and interpolates linearly in between, with full marks at 100 and zero at 0. That way a B is a B whether the raw boundary was 53 or 58. A* (PUM 90) is awarded on the overall subject aggregate, not on a single component, so this component-level tool uses the published A–E thresholds.
New to the term? Read Percentage Uniform Marks explained for the full picture.
Want to know where each mark went?
A PUM tells you the grade. MarkScheme shows you why — upload your paper for mark-by-mark feedback against the real Cambridge scheme.
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