IGCSE and GCSE Grade Converter: 9–1 and A*–G

Using the converter

Start with the scale actually printed on the certificate, not the one the family is used to. Four are in circulation among the students we teach: Cambridge IGCSE on A*–G, Cambridge IGCSE on 9–1, Edexcel International GCSE on 9–1, and the GCSE sat in England on 9–1. Choose one, choose the grade, and the other three scales fill in.

The three 9–1 scales are the same scale, so no conversion happens between them — the tool says so rather than pretending to calculate something. They are still separate qualifications with separately set boundaries, which is why a grade 7 from Cambridge and a grade 7 from an English board are the same standard on paper without being the same paper.

The uniform mark box is optional and only applies to one of the four. Cambridge issues a percentage uniform mark for IGCSE on the A*–G scale, for O Level and for International AS and A Level, and not for IGCSE 9–1. Enter it on the wrong scale and the tool explains why there is nothing to read rather than reading something anyway.

• Cambridge IGCSE A*–G — Mathematics is 0580, International Mathematics is 0607
• Cambridge IGCSE 9–1 — Mathematics is 0980, the same syllabus content on a different scale
• Edexcel International GCSE 9–1 — Mathematics A is 4MA1, Higher tier targeted at 9–4 and Foundation at 5–1
• GCSE in England 9–1 — Edexcel 1MA1, AQA 8300, OCR J560

Why there are only three fixed points

When England moved GCSEs from letters to numbers, Ofqual did not build a translation table. It aligned three thresholds and left the rest to fall where the statistics put it: the bottom of grade 7 was set at the bottom of the old grade A, the bottom of grade 4 at the bottom of the old grade C, and the bottom of grade 1 at the bottom of the old grade G. Cambridge did the same for its 9–1 IGCSEs, stating that the standards at the thresholds of grades 7, 4 and 1 are the same as the standards at the thresholds of grades A, C and G.

That leaves six grades with no letter equivalent, and the arithmetic explains why: nine grades cannot map onto eight letters without one of them being split. Grades 9, 8 and 7 share the ground the old A* and A covered, so a grade 8 is genuinely between an A and an A* with nothing published to place it. Grade 9 was deliberately set above the old A*, which is why a school that reports "nine A* equivalents" is reporting something the awarding bodies never claimed.

The bottom of the scale is compressed the other way. Grades 3, 2 and 1 cover what D, E, F and G used to cover, so the tool shows a grade 2 as sitting across the old E and F rather than picking one.

What this deliberately does not do

It does not print a one-to-one map. Every table that shows 9 = A*, 8 = A, 7 = B is inventing seven of its nine rows, and a family that plans a sixth-form application around one of those rows is planning around a number nobody published.

It does not turn a raw percentage into a grade. Cambridge, Pearson and the English boards all set raw-mark boundaries after the papers are marked, fresh for each series, so 68% means one grade in one June and another in the next. The uniform mark is different — it is a fixed scale, which is exactly why it can be read — and it only exists where Cambridge issues it.

It does not state a national equivalency. IBCC in Pakistan converts letter grades to marks for its equivalence certificate, and the UAE Ministry of Education runs its own equivalency process; both set their own rules, both change them, and both are the right place to ask. What the tool does say is where IBCC's published conversion is fixed — A is 85, B is 75, C is 65, D is 55, E is 45 — and where it is not: the A* figure is set per subject per examination session and IBCC publishes it separately each year.

Where families go wrong

The most expensive mistake is reading a grade 4 as a safe C. It is a low C by construction, because the alignment was made at the bottom of both grades. A student who needs a comfortable C for a sixth-form subject needs a 5, and a lot of disappointed August phone calls come from that one row of the table.

The second is expecting a percentage on a 9–1 statement of results and reading the tool's silence as a fault. Cambridge does not issue a uniform mark for IGCSE 9–1 at all. The number in brackets that a friend on the A*–G scale is comparing notes about simply does not exist on the other certificate.

The third is assuming the scales are interchangeable for admissions. UK universities and sixth forms have said they treat 9–1 and A*–G candidates equally, and Cambridge reports the same from universities about its two grading options — but the school's own subject bar is set locally, in whichever scale that school thinks in. Ask in the scale they use, not the one on the certificate.