How do the 9-1 GCSE grade boundaries work in England?

GCSE results day is approaching for hundreds of thousands of students in England, Wales and Northern Ireland.

In England, GCSEs are graded using a numerical system from 9 to 1, having previously used an A-to-U letter system.

Exams are graded differently in Wales and Northern Ireland and still use a letter system, while students in Scotland take Nationals instead of GCSEs.

The 9-1 grading scheme was brought in alongside an overhaul of the curriculum in England in 2014.

The rollout began in 2017 with three subjects - English language, English literature and maths - being the first to be graded in numbers. By 2020, all subjects were using the new grading system.

The highest grade is 9, while 1 is the lowest, and U means "ungraded".

The number scale is not directly equivalent to the old letter one. However, the two scales do meet in certain places:

three number grades - 9, 8 and 7 - correspond to the two previous top grades of A* and A

That means that a 9 is a high A*, an 8 is a low A* or high A, and a 7 is a low A.

A 3 is a D or high E, a 2 is a low E or high F, and a 1 is a low F or G. And a U is still a U.

Grade boundaries dictate what the lowest mark is you can get to achieve a grade.

They are decided by examiners each year. Exam boards publish grade boundaries on results day.

While grades 1-3 technically count as a pass, many sixth forms insist on a minimum number of 5s or 6s as a condition of entry for further study.

The government's school league tables , external are based on the percentage of pupils who achieve a 5 or above in English and maths GCSEs.