Calculation methodology

Comparison percentages

Boundary percentage = 100 × published qualification boundary ÷ the published qualification maximum. We keep each board, code, tier and entry option separate. Rankings use unrounded values, with ties sharing a competition rank. Calculated percentages and derived comparisons are our calculations.

The percentage tool checks which thresholds the chosen percentage crosses. This is not a prediction of performance in another subject. Read the comparability explanation.

Total-mark checkers do not combine raw papers: they require the final qualification-scale total. For weighted qualifications, obtain that total from the school or awarding organisation.

Qualification totals

The calculator adds the marks you enter for completed or estimated components. Leave a box empty for a paper you haven't taken yet. It then subtracts your entered total from the selected qualification boundary.

The calculator divides the marks still needed by the marks still available, then rounds the requirement up to the next whole mark because grade boundaries use whole marks.

Where an awarding organisation scales components before calculating the qualification total, the calculator applies that weighting first. Pearson Edexcel GCSE Drama, for example, scales Components 1 and 3 from 60 raw marks to 96 weighted marks each.

Published series

An exact-year calculation answers a historical question: what grade would these marks have received under that June series? The GCSE and A-level calculators include the official June 2026 boundaries.

The recent-range view uses 2024–2026 for both GCSE and A level. June 2022 remains available as a separate exact-year comparison because grading arrangements were transitional.

Qualification boundaries

Final grades are awarded from the combined qualification mark. Notional component boundaries can help with paper-level analysis, though individual paper grades do not combine to create the final qualification grade. The calculations on this site use subject-level qualification boundaries.

Tiers, options and endorsements

Foundation and Higher tiers have separate grade scales and boundary records. AQA Physics optional topics have separate qualification rows where the board publishes them. The calculator keeps spoken-language and practical endorsements separate; they add no marks to the numerical grade.

Movement and the 2027 crystal ball

Boundary chaos uses the 2024, 2025 and 2026 June series where all three share a qualification code, entry option and total scale. It shows the range, population standard deviation and largest adjacent-year movement. Three years describe a short recent window, not a long-term law.

The 2027 tool freezes a selected simple model and its input snapshot. Its method, held-out historical errors and the limits of the historical-error band are available on the 2027 forecast page.

Limits

A future boundary cannot be derived from earlier years with certainty. Paper difficulty, cohort performance and awarding decisions all affect the final value. Estimated marks from an unofficial mark scheme may also change before results are issued.