Exam info · How marks work
How exam marks work
Every UK exam board (AQA, Edexcel, OCR, WJEC, CCEA) uses the same shorthand on their mark schemes. Once you know it, you can read any mark scheme and instantly see where the marks come from — and where you're losing them.
The four main codes
- M1
Method mark
You showed the correct method or approach. You can earn this even if your final number is wrong.
For "Find HCF of 60 and 90", writing 60 = 2² × 3 × 5 and 90 = 2 × 3² × 5 earns the method mark — you used the right technique.
- A1
Accuracy mark
Your answer is correct. You only earn this if you also earned the corresponding method mark — A-marks depend on the M-mark above them.
Continuing the HCF example: writing HCF = 2 × 3 × 5 = 30 earns the accuracy mark — but only if you showed the prime-factorisation method first.
- B1
Independent mark
A standalone mark. You earn it by getting one specific thing right, with no method needed and no dependence on other marks.
Stating "Y is irrational" or "the gradient is 3" — single facts that score 1 mark each, regardless of working shown.
- C1
Communication mark
Awarded for explaining your reasoning clearly in writing. Used in extended-response and proof questions.
"Therefore the sequence converges because each term is less than the previous." Clear logical explanation = C1.
Common suffixes
These appear after the main code, e.g. A1 ft or B2 oe.
- ftFollow-through
If your earlier answer was wrong, you can still earn marks later by using your wrong answer correctly. Stops one mistake costing you everything.
- oeOr equivalent
Any equivalent form is accepted. ¾ = 0.75 = 75% all earn the same mark.
- caoCorrect answer only
No follow-through. The exact answer is required.
- depDependent
Only awarded if a specific earlier mark was awarded.
- soiSeen or implied
You earn the mark even if you don't state it explicitly, as long as your working makes the step obvious.
A worked example
From a real GCSE Maths question — "Solve 2x² − 7x + 3 = 0 using the quadratic formula. (3 marks)"
Identify a = 2, b = −7, c = 3.
Discriminant: b² − 4ac = 49 − 24 = 25 (M1)
x = (7 ± 5) / 4 (M1)
x = 3 or x = ½ (A1)
Two method marks (one for the discriminant, one for the formula application), then one accuracy mark for both correct answers. Even if the final numbers are wrong, you can still earn 2 of 3 marks for showing the method clearly.
Why we keep the codes
We mirror the official exam-board notation in our worked solutions on purpose. When you meet these codes in a real mark scheme on results day, you'll already know exactly what they mean — and what you needed to write to earn each one.