Calculating unitised grades

The difficulty of unitised qualification exam papers may vary from year to year. In order to ensure fairness and consistency across years and within subjects, the raw examination marks are converted into a common scale.

This scale is known as the uniform mark scale/score (UMS). It gives a fixed scale with common boundaries that are unchanged year on year and is used to make the marks compatible and comparable. The UMS grade boundaries are available on our grade boundaries page.

Sally and Peter both sat an A Level Humanities unit, but in different years. 

There are four, equally weighted units needed to achieve the qualification. Both papers are marked out of 80 and both students score 61. But, as Sally's exam included more complex questions than Peter's, the grade boundary for achieving an A grade is set at 61. Peter's exam was relatively straightforward and the A boundary is set at 64. 

Therefore, for this unit, Sally achieves an A and Peter achieves a B. Their marks are converted to UMS (out of a maximum of 80) as shown below. 

Peter therefore has 61 raw marks with the A boundary for his unit set at 64. When this is converted into UMS, he has 60 uniform marks. 

Sally also has 61 raw marks with the A boundary for her unit set at 61. When this is converted into UMS, she has 64 uniform marks.

1. Students sit the exam and the script is marked by an examiner according to a set of strict criteria. The examiner then calculates the raw mark.
2. An awarding meeting takes place, with a group of experienced senior examiners comparing papers from that year with previous papers and statistics. Using their professional judgement they decide what the grade thresholds should be.
3. The raw marks for the unit are converted to a UMS.
4. The overall qualification grade is calculated by adding together the uniform marks achieved in the individual units. This gives candidates a final uniform mark which is compared against the overall UMS grade boundaries.

When calculating a candidate’s qualification result, we:

• Find all the candidate’s unit results for the specification along with any previous certification results.
• For AS and A Level and Level 3 Certificate, if the candidate is re-certificating, check they have taken something new since their last certification.
• Find all the valid unit combinations for that certification.
• For GCSE, check the 100% terminal rule has been satisfied.
• Apply any other entry rules relevant to that specification. For example: common units in some GCSEs; locking in AS and A Level Maths and Classics; certification dependencies in AS and A Level Maths.
• Add up the unit UMS scores for each valid combination and compare it with the qualification UMS grade boundaries.
• Choose the combination that gives the best grade and highest UMS score.

Grades are then awarded. Both the unit uniform marks and grades, and the final uniform mark and grade are given on the results slip.

For more information about how we calculate the A Level A*, you can read the guide on the following page: