This summer, almost all GCSEs will be graded 9 - 1 after the biggest shake-up of the exams for a generation.
Though some subject results have been in numerical form since 2015, this year is the first time the majority of subjects will be graded by the new system.
What is the difference between the two systems?
The two systems are strikingly similar but the obvious difference is letters have become numbers and there is a wider range of grades.
This means top performers can now receive a 9 for their hard work, which is higher than an A*, but for those less academically able the bottom grade remains the same.
For most subjects, each grade will translate into one GCSE qualification but for some science students that will not be the case.
Why has the system changed?
In a shake-up to the system, the government has designed GCSEs for two-years of study, adding weight to the exams at the end of the course.
New GCSE content is said to be more challenging so 9s are reserved for the year's top achievers, creating a new bracket above what would otherwise be A*.
The reforms help to differentiate between students who achieve the higher grades that in the past were C, B, A and A*. Instead of there being four grades considered a pass there are now six.
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When will all subjects be graded under the new system?
Summer 2019 will be the first time the vast majority of subjects are graded under the new system.
English language, English literature, and maths became the first subjects to begin teaching for the new exams in 2015. By the time those students finished their course in 2017, they were the first to get their results in numerical form.
From the start of 2018 all subjects will begin teaching for new GCSE exams so by 2020 all students in England will receive their grade in numerical form.
What you can do if you don't make the grade:
If you're unhappy about your number, you can appeal to your exam board as part of the 'Reviews of Results' service.
Each exam board has a different price per unit or paper, and it's worth checking with your exam board to find out the deadline for requesting a review.
The mark will be changed if the reviewer thinks it’s wrong - but the new mark may be higher or lower than the original.