Your marking assistant.
Photograph a pupil's handwritten paper, add your own mark scheme, and Rubidium marks it one mark at a time, with a reason for every single mark.
- Personalised feedback. Specific comments on what each pupil actually wrote.
- Class overviews. Strengths, weaknesses and topics to revisit, with a spreadsheet to download.
- Learns from your marking style. Comments pick up your tone and level of detail, and your mark scheme still decides the marks.
- Developed with teachers. Shaped by teachers' feedback, so it fits how marking really works.
3 free tokens when you sign up. No subscription, and no card needed to start.
73% of secondary teachers said they spent too much time marking and correcting pupils' work.
Department for Education, Teacher Workload Survey 2016.
Rubidium does the first pass. You keep the judgement.
Three steps, and no spreadsheet to build.
Photograph the work
Snap each page with your phone or upload a PDF. Add your own mark scheme once, then reuse it for the whole class.
Rubidium marks it against your scheme
Every mark is listed on its own, with a reason that points back to the mark scheme.
You check, copy and move on
Read the reasons, spot anything you disagree with, then copy comments straight into reports.
Built so you can trust what you read.
AI can make mistakes, so Rubidium shows its working and keeps you in charge.
A reason for every mark
Each mark is listed on its own with a plain explanation, so you can check the AI in seconds.
Your mark scheme, your rules
Upload the scheme you actually use. Rubidium marks against it, not against its own idea of a good answer.
Feedback pupils can read
Short, specific comments written for readers aged 12 and over, with subject terms kept exactly as your mark scheme uses them.
Marks in your style
Upload up to three papers you have already marked and Rubidium picks up your tone and level of detail. The mark scheme still decides the marks.
A class overview
See the class's strengths, weaknesses and topics to revisit, and download the results as a spreadsheet.
Your register from a photo
Photograph your register and add the whole class in one go.
Copy and paste
Copy a whole result or a single comment straight into a report or an email.
Safety nets
You are not charged if the paper cannot be read, the marks do not add up or marking fails. You can also re-mark the same pupil once for free.
AI can be wrong. That is why you stay in charge.
Rubidium never sends results to pupils or parents. Everything stays with you until you copy it out.
Built around UK GDPR
A privacy policy that says exactly what is kept, why, and who handles it.
Deleted after 6 months
Scanned papers and their results are deleted automatically 6 months after upload.
Private by default
Pupil papers are stored privately, and one teacher cannot see another teacher's data.
Yours to delete
Close your account in the app and your classes, papers and results go with it. Nothing is sold or used for advertising.
Pay for the papers you mark. No subscription.
One token marks one answer, however many marks it is worth.
If marking fails for any reason, your token is returned automatically.
Create a free accountQuestions teachers ask
Will it replace my marking?
No. It does the first pass and shows its reasons. You decide which marks stand.
How accurate is it?
It can make mistakes, as any AI can. That is why every mark comes with a reason that points back to your mark scheme. If the marks do not add up, Rubidium does not save the result and does not charge you.
What if it cannot read the handwriting?
Rubidium tells you plainly, does not charge a token, and suggests retaking the photo in good light. Very faint pencil and very small writing are the hardest to read.
What happens to pupil data?
Papers are stored privately and deleted automatically after 6 months. The privacy policy lists every provider involved and what each one handles.
Which exams does it cover?
It is built for GCSE and A-level practice papers. If you can photograph the work and the mark scheme, you can try it.
How much does it cost?
New accounts get 3 free tokens. After that, 40 tokens cost £7.99 and 100 tokens cost £16.99. There is no subscription.