As hundreds of thousands of UK pupils get results, the plunge in top grades will affect an estimated 75,000 - with about 50,000 fewer getting at least a basic pass in six GCSEs.
Grades for A-level students had been expected to drop back from 2021 levels - when pupils were assessed by their teachers - as part of a transition year.
Some 20,360 pupils in England, Wales and Northern Ireland found out today that they were unplaced and therefore eligible for Clearing, based on exam results.