Accuracy You Can Trust
We believe transparency matters. Rather than making vague claims, we publish our real accuracy data so you can decide for yourself.
How We Compare
| Metric | GRADED PRO | Human Markers* |
|---|---|---|
| Correlation with professional markers | 0.97 | ~0.70 |
| Average error on structured questions | 0.2 marks | Not published |
| Average error on essay questions | ~2 marks | 5.6 marks |
| Marks within tolerance | ~80% | ~45% |
*Based on a Cambridge Assessment study in which 200 English scripts, already marked by a chief examiner, were independently re-marked by experienced markers.
Structured Questions
Our system excels on questions with defined correct answers — the kind that make up the majority of assessments.
to the examiner
of the examiner
per question
Whether it's a 1-mark calculation or an 11-mark multi-step problem, the AI consistently matches professional marking standards.
Extended Writing & Essays
Levelled questions — where markers use band descriptors to assess quality — are harder for any marker, human or AI. Our system uses a structured levelling process modelled on how trained markers work: identify the best-fit level, then position within it.
- Average error of around 2 marks on levelled questions
- 97% correlation with professional markers across all question types
- Significantly outperforms the average experienced human marker
What This Means For You
AI marking is not a replacement for your professional judgement — it's a tool that handles the heavy lifting so you can focus on what matters.
Short-answer questions, calculations, retrieval tasks, and structured responses across all subjects. On these question types, the AI marking is highly reliable and ready to use as-is.
Extended writing and essay-style responses at the very top of the mark range. The AI occasionally under-marks the strongest responses by a few marks. A quick review of your highest-performing students' work is good practice.
Use AI marking to get a fast, accurate first pass across a full class set. Moderate a sample — just as you would with any marking — and adjust where needed. Teachers who use this approach typically report saving 50–70% of their marking time.
Not Just Exams
Our accuracy benchmarks are based on formal examination papers, but Graded Pro is built for everyday marking across all types of student work. The same AI that matches chief examiner standards on exam scripts delivers consistent, rubric-linked feedback on:
- Homework — weekly assignments marked and returned the same day, with actionable next steps
- Classwork and in-class tasks — quick, consistent feedback while the learning is still fresh
- Termly tests and mock exams — full cohort marking with detailed breakdowns by question
- Coursework drafts — formative feedback that helps students improve before final submission
- Past paper practice — students get instant, exam-standard feedback on every attempt
Wherever there's a rubric or mark scheme, Graded Pro delivers accurate, detailed feedback — whether the stakes are high or the goal is simply helping students learn from their work.
Our Commitment
We continuously test and improve our marking accuracy. We don't claim perfection — no marker, human or AI, achieves that. What we do promise is transparency about where the system performs well and where it has limitations, so you can use it with confidence.
See For Yourself
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