Parents often see grades like A*, 8, 6 or “38/45” – but never see the raw marks or scaled scores behind them. This guide explains, in plain English, how raw marks, UMS, percentage uniform marks (PUM) / UTR-style scores and IB 1–7 grades all fit together for Cambridge, Edexcel and IB Diploma students in 2026.
1. Raw Mark – the starting point
The actual number of marks a student scores on the paper – before any grade boundaries or scaling.
What is a raw mark?
Raw mark = the literal score on the exam. If a paper is out of 100 and a student scores 78, their raw mark is 78/100.
Raw marks are what examiners work with first. But raw marks alone don’t decide the final grade, because each exam series can be a little easier or harder than the last.
Why raw marks are not enough
To keep things fair, exam boards (Cambridge, Pearson Edexcel, IB) set grade boundaries after they mark the scripts. Boundaries say, for example: “from this raw mark upwards is a B”.
That way, a slightly harder 2026 paper doesn’t give lower grades than an easier 2024 paper for the same level of performance.
2. UMS – mainly Edexcel (Pearson), not Cambridge
The Uniform Mark Scale is / was used mainly by Pearson Edexcel to standardise raw marks.
What is UMS?
UMS (Uniform Mark Scale) converts raw marks onto a standard scale (often out of 100 or 200) so that:
- Different exam sessions can be compared fairly
- Modular units can be added up consistently
Example: a raw mark of 72/100 might be converted to 85/100 UMS if that best reflects where the student sits in the grade band for that session.
Important: Cambridge IGCSE and Cambridge International A Level do not use UMS. UMS is primarily a Pearson Edexcel concept.
3. Cambridge Percentage Uniform Mark (PUM) / UTR-style scores
Cambridge’s scaled score out of 100 that shows where your child sits inside their grade.
What is PUM?
Cambridge’s official term is Percentage Uniform Mark (PUM). It is a scaled score from 0–100 that shows whether a student is at the top, middle or bottom of their grade.
For example, at IGCSE or A Level, the PUM ranges are typically:
- A*: 90–100
- A: 80–89
- B: 70–79
- C: 60–69
- etc.
These are percentage uniform mark ranges, not raw-mark percentages. The board converts raw marks into PUM after setting grade boundaries.
Example – illustrative only
In a typical Cambridge subject, you might see something like this on a statement:
| Raw Mark | PUM | Grade |
|---|---|---|
| 92 | 96 | A* |
| 85 | 90 | A* |
| 76 | 84 | A |
| 68 | 78 | B |
Note: These numbers are for illustration only – real conversions vary by subject and exam session, and Cambridge publishes them separately.
What parents actually see
On Cambridge statements of results, parents usually see the final grade (A*, A, B, etc.) and the percentage uniform mark for each syllabus. Some school systems or portals label this with their own term (sometimes similar to “UTR”), but the underlying idea is the same: a scaled score from 0–100 that supplements the grade.
4. IB Diploma – 1–7 scale and 45 points
Different labels, same idea – convert raw marks into a stable grade scale.
1–7 subject scale
In the IB Diploma Programme, each subject is graded on a 1–7 scale. Raw marks are converted to 1–7 using boundaries set after each May / November session.
Typical grade meanings:
- 7 – Excellent
- 6 – Very good
- 5 – Good
- 4 – Satisfactory
- 3–1 – Mediocre to very poor
TOK, EE and the 45-point maximum
Six subjects (up to 7 points each) give a maximum of 42 points. Theory of Knowledge (TOK) and the Extended Essay (EE) are graded A–E and combined via a matrix to add 0–3 bonus points.
This gives the famous maximum 45 points. To be awarded the Diploma, students must reach at least 24 points and satisfy several additional conditions (such as no very low grades in HL subjects).
5. How grades are actually awarded – side by side
The flow from raw mark to final grade looks slightly different by board, but the logic is the same.
Cambridge (IGCSE & International A Level)
- Raw mark
- Grade boundary is applied (e.g. raw ≥ X = grade B)
- Grade awarded (A*–G at IGCSE, A*–E at A Level)
- Raw mark converted to PUM (0–100), which shows where the student sits inside that grade
Edexcel (International GCSE & A Level)
- Raw mark
- For linear 9–1 IGCSEs, Pearson publishes raw-mark grade boundaries per series
- Grade awarded (9–1 or A*–E)
- For modular / older specs, raw marks may be converted to UMS for aggregation and reporting
IB Diploma (IBDP)
- Raw mark in each subject
- Grade boundaries convert raw marks to 1–7 subject grades
- TOK + EE grades (A–E) convert to 0–3 bonus points
- 6 subjects (max 42) + up to 3 bonus = total /45
6. Why scaled scores (PUM / UMS / IB scaling) matter for parents
These numbers show real progress inside a grade – not just when the letter or number changes.
Same grade, different story
Consider a student whose Cambridge IGCSE report looks like this:
| Session | Grade | PUM / scaled score |
|---|---|---|
| Oct 2025 | B | 72 |
| Mar 2026 | B | 79 |
On paper the grade is still B, but the scaled score has moved from 72 → 79. That’s a real improvement, just short of an A band – a powerful message for both motivation and planning.
Tutors and schools can use these scaled scores (PUM, UMS or IB’s internal conversions) to:
- Track progress accurately across multiple exam sessions
- Set realistic targets (e.g. “move from mid‑B to low‑A range”)
- Build personalised learning plans that focus on specific gaps rather than just chasing a headline grade
Turn exam data into smart decisions
Tutopiya helps families interpret raw marks, scaled scores and grade boundaries – and turn them into a step‑by‑step plan for IGCSE, A Level and IB success.