Students in England, Wales and Northern Ireland will be opening A-level, T-level and BTec results this morning.
It is the first time since 2019 that A-level grades are being based on public exams, after two years of cancellations because of Covid.
Overall grades for A-levels are expected to be lower than 2020 and 2021, when grades based on teachers' assessments led to a boom in top marks.
Ofqual has said results would reflect "a midway point" between 2019 and 2021.
