A-Levels run from A* down to E, with U below. But the letter on the certificate hides a marks calculation underneath — and the A* has a rule most students only discover too late. Here is exactly how it works.
Quick answer: A-Levels are graded A*, A, B, C, D and E, with U (ungraded) below E. For international A-Levels the grade comes from a Uniform Mark Scale (UMS): roughly 80% of total marks earns an A, 70% a B, 60% a C, 50% a D and 40% an E. The A* is different — it needs an A overall (80%+) plus 90%+ across the second-year (A2) units, so it can never be secured on the AS year alone.
A-Levels are graded on a six-point letter scale from A* at the top to E at the bottom, with U (ungraded) below that. That much is well known. What trips students up is the machinery underneath: the letter is not your raw exam percentage — it is the output of a Uniform Mark Scale, and the prized A* follows a separate rule of its own.
Almost all of our students sit international A-Levels — either Cambridge International (CAIE) or Pearson Edexcel International Advanced Level. This guide explains how those grades are built, why your mock percentage and your real grade rarely match, and the one calculation that decides whether an A becomes an A*. For where A-Levels sit in the bigger picture, see what comes after IGCSE and IB Diploma vs A-Levels.
From highest to lowest, a full A-Level is awarded as:
An AS Level — the standalone first year — runs only from A to E. There is no A* at AS; the A* exists only at full A-Level.
International A-Levels are marked on a Uniform Mark Scale (UMS). Your raw marks on each paper are converted into UMS points so that results are comparable across papers and exam sessions of slightly different difficulty. A complete A-Level is worth 600 UMS — 300 from the AS year and 300 from the A2 (second) year. The standard grade thresholds are fixed proportions of that total:
| Grade | UMS (out of 600) | Share of marks |
|---|---|---|
| A* | 480+ and 90% on A2 | A overall + 270/300 on A2 |
| A | 480 | 80% |
| B | 420 | 70% |
| C | 360 | 60% |
| D | 300 | 50% |
| E | 240 | 40% |
This is why an 82% raw mock can come back as an A while a 78% comes back as a B — the boundary is set in UMS, not in your raw percentage, and the conversion shifts a little each session.
The A* is not simply "a very high A". It has two conditions, and you must hit both:
The practical consequence is large: a brilliant AS year cannot bank you an A*. A student who scores 95% at AS but drifts to 85% in the A2 papers lands an A, not an A*, because the A* is decided on the A2 half. The strategy that follows is simple — protect a strong AS, but treat the A2 units as where the A* is actually won.
For modular international A-Levels, AS and A2 each contribute 50% of the final grade. Strong AS marks give you a cushion, but they cannot lift you above an A on their own. UK domestic A-Levels are now linear — all exams sit at the end of two years and the AS no longer counts toward the A-Level — but the A* logic is the same in spirit: it rewards top performance across the full A-Level content.
Both boards use A*–E and the same UMS thresholds, but they reach them differently. Edexcel International is modular — you sit units across January, June and October, and you can resit individual units, with the better mark counting. Cambridge International is staged — you sit AS and A2 components in June or November, and a resit means retaking a whole component, not a single paper. We unpack this fully in Cambridge vs Edexcel A-Levels and A-Level retakes and resits.
Boundaries are published after each session, not before. Examiners review how the cohort performed and how hard the paper proved, then set the raw-mark boundary for each grade so that standards stay comparable year to year. A harder paper means a lower boundary; an easier one means a higher boundary. This is why past-paper raw scores are a guide, not a guarantee — judge progress by the grade band, not the exact percentage.
For UK university applications, A-Level grades convert to UCAS tariff points: A* = 56, A = 48, B = 40, C = 32, D = 24, E = 16. Three A*s therefore total 168 points — though most universities make offers in grades (for example "A*AA"), not points.
Take a student with 285/300 UMS at AS and 265/300 at A2 — a total of 550/600, comfortably an A. But that A2 figure is 88%, just short of the 90% (270/300) the A* demands, so the grade is an A, not an A*. Nudge the A2 marks to 272 and the same student crosses into A*. That five-mark swing on the second-year papers is the entire difference between the two grades — and it is exactly why focused A2 preparation is the highest-value work in the whole course.
Both Cambridge and Edexcel offer post-results services — a clerical re-check or a full review of marking — within published deadlines after results day. A review can move marks up, leave them unchanged, or, occasionally, down, so it is most worth requesting when a grade falls just below a boundary and a university offer depends on it. Priority services exist for cases where a confirmed place is at stake, with faster turnaround.
University offers are written in grades, not percentages — "A*AA", "AAB" and so on. As a rough guide an A is around 80% of the UMS, a B 70% and a C 60%, but the raw-mark boundary shifts every session, so the same percentage can be different grades in different years. Treat the grade, not the percentage, as the real currency, and always check each course's exact requirement rather than assuming a standard offer.
The A* is decided on your second-year units — that is exactly where targeted 1-on-1 work pays off. Our Cambridge and Edexcel A-Level tutors map your current UMS band and build the route to A/A*. Free diagnostic trial.
💬 Book a Free Trial on WhatsAppOfficial sources: Cambridge International AS & A Level grade thresholds · Pearson Edexcel International A Level results explained.
