Rules of thumb: Pre 1988 O levels should be treated as 1988 GCSE grades. Edexcel International GCSE is equivalent to GCSE. Cambridge IGCSE could be viewed as about one grade higher.
Over time, different exams have changed levels, names and grades. This causes confusion and unfairness. Employers may be unfairly discriminating against older workers or admissions officers against mature students if they do not realise the greater value of some of the older examination standards. Parents may be offering poor advice to their children on the suitability of further education or career options, based on an outdated notion of the value of qualifications (for example based on the mistaken belief that the child is performing better than the parents themselves did).
This website aims to offer some comparison between different national exams at various grades taken at different times. It is intended to be balanced and fair rather than make a point, we err on the side of assuming exam levels are the same taking assumptions which are moderate and not in any way exaggerated. We transparently explain the basis for the conversion tool here, which is offered in good faith but with no guarantee. We leave the user to judge whether the basis we outline is sound.
As an example of moderation, we rate grades using the average marks obtained by a candidate with a given grade to position them. The alternative is using the threshold mark for a grade which would give a much more severe comparison. Using a threshold just seems too severe even though logically a grade is worth as little as the lowest mark which could attain it; with a threshold approach the intervention of a Welsh politician to lower grade boundaries would have downgraded the value of the whole cohort by an entire grade. We also discount any effect that broadening exam intake may have on demographically lowering the calibre of candidates since we find evidence that social exclusion dominated over ability in historical intake. Overall therefore we understate the value of older exams.
Some exam boards for A level and GCSE have always been regarded as harder than others. However it is hard to find evidence for change in relative position over time and we have not tried to model for this effect.
For O levels and GCE exams (sat in the UK prior to 1988) we suggest that O level grades are considered equivalent to the same 1988 GCSE exam grade. There seems to be evidence of some declining attainment before that but there was no step change in 1988 and the two tier exam system prior to 1988 is very difficult to evaluate because it was simply untrue that the bright children took the harder exam. For GCE grades officially grade 1 was equivalent to a C grade in O level but there is some evidence that a grade 1 was closer to a B grade and a grade 2 a C grade because separation between the exams was as much social as on pure ability.
Edexcel offer an International GCSE which they say is intended to be entirely equivalent in level to a modern GCSE and so should be treated as equivalent. Cambridge (CIE) offers an IGCSE which is supposed to be closer in standard to the old O level exams. Comparing to GCSE is difficult because of the effects of retaking modules but it is possible to compare to the Edexcel International GCSE, which is a straight exam. Looking through the papers and marking schemes in recent exams the Cambridge IGCSE (which, for example, appears harder than the Edexcel exam most notably in not providing a formula sheet) we feel some upward adjustment in grade comparison might be appropriate; for the sake of argument therefore we suggest Cambridge IGCSE is worth one grade higher than GCSE.
This tool is really aimed at employers. Employers must remember that the maximum grade achievable in a year was the highest attainment possible by a student. Recent students were given no opportunity to achieve higher and may have a much higher level of attainment. There will be students who finished their exams an hour early scoring nearly full marks amongst those who struggle to make their grade. Those brightest students are still there and they are the ones who have been most let down by the compression of three pass grades into A* over the years.