How Are IGCSE Grades Calculated? A* to G and 9–1 Explained

Two things about IGCSE grading surprise people, and both matter more than the scale itself.

The first is that thresholds are not fixed in advance. The second is that in several subjects your grade is capped before you sit the paper, by which tier you were entered for.

What are the two IGCSE grading scales?

9–1, where 9 is the highest, is the current scale in most contexts.

A* to G, where A* is the highest, is the legacy scale and still appears — in older material, in some boards and contexts, and in a great deal of advice written a few years ago.

They are not a simple one-to-one translation, and you will meet both when reading around. Rough correspondences circulate online; treat them as approximate rather than exact, and use whichever scale your own board reports.

A practical use for this: if a prospective tutor discusses your target in the old scale without noticing which one you are on, they have not taught the qualification recently.

Are IGCSE grade boundaries fixed?

This is the part that changes how you should revise.

The mark needed for each grade is decided for each subject in each exam session. It is not a fixed percentage carried over from last year. Papers vary slightly in demand, and the thresholds move to account for that.

So the sentence "you need 80% for a 7" is not a real fact, however often it is repeated. Past thresholds tell you roughly where a subject has sat historically. They do not tell you what this year's will be.

What follows from that is simple: aim above the boundary you think you need, because you cannot know it in advance.

How does tiered entry cap your grade?

Several IGCSE subjects are entered at different tiers — the names vary by board, commonly something like core and extended, or foundation and higher.

The tier determines which paper you sit, and the range of grades available differs by tier. The lower tier does not offer the full range of top grades.

This is the single most important thing to check, and a surprising number of families do not know which tier their child is entered for. If a target grade is not available on the tier they are on, no amount of work reaches it.

Ask the school. Ask early enough that a change is still possible, which usually means well before the final term.

Boards are not interchangeable

IGCSE is offered by more than one examination board. Syllabus content, paper structure and thresholds differ between them.

This matters when you are reading advice, using past papers, or choosing a tutor. Past papers from the wrong board will teach you the wrong paper structure. A tutor fluent in one board may be guessing at another.

Find out which board your school enters you for before doing anything else.

What actually determines the grade

Within all that, the marks come from ordinary places:

Method, shown. Many subjects award marks along the working. Reaching the right answer without showing the route loses marks that were genuinely earned. This is the cheapest improvement available in most IGCSE subjects.

Answering the command word. Describe and explain want different things. State wants a fact, not a paragraph.

Answer length matched to marks. A six-mark question answered in two marks' worth of detail has capped itself.

Coursework or practical components, where the subject has them. Check what proportion, and whether it is already banked.

How do you find your board and tier?

Ask the school directly, and ask early. Both change what should be practised, and both are routinely assumed rather than checked.

The tier question is the one worth asking first. If a target grade is not available on the tier a student is entered for, no amount of work reaches it — and that is fixable only before the entry deadline.

How should you use past papers?

Past papers are the backbone of IGCSE preparation, and most students use them badly — as a topic quiz rather than as a rehearsal.

Use them from the right board, sat complete and under time, from earlier than feels sensible, and marked against the markscheme rather than against a memory of what you meant.

Then separate two numbers: marks lost because you did not know something, and marks lost to method, command terms or answer length. The second number is almost always larger than students expect, and it is the one that moves quickly.

FAQ

If you are still weighing curricula rather than papers, IGCSE vs ICSE covers what actually differs between them, and IB grading runs on a different logic again — a total out of 45 rather than a threshold per subject.

If you do not know your board and tier, that is the first thing worth establishing. See how it works — the first session is free and starts with a marked paper.