AI writing correction

Correct student writing with AI. Choose the right modules.

Choose the support you need for photographed student writing: review language errors, prepare feedback or request suggested points against your criteria. Learn what each module delivers and what you need to check yourself.

Try four base corrections free

No credit card · up to 2 pages per base correction · no subscription

Example

Correction should say more than “wrong” — it should say why.

Illustrative example · English

Example correction

My summer holyday¹ was great. I has went² to the beach every day.

¹ Spelling: holiday
² Tense: went

How it works

From photo to correction in three steps.

01
Take a photo
Photograph one or several pages on your phone — handwritten or typed.
02
Let Tuba read it
Tuba transcribes the content into one coherent text before correction begins.
03
Review the correction
Errors, reasons, feedback and grading suggestions appear side by side.

Handwritten or typed

Use phone photos of handwritten pages, typed work or printouts — no manual retyping before correction.

Built for teachers

Error analysis, feedback and grading suggestions can follow your own criteria. The final grade stays with you.

Privacy by default

Tuba does not store original images permanently. AI analysis uses Anthropic and may involve processing in the US. See Privacy and Processors for retention and deletion details.

What is included, and which modules do you need?

The base correction covers language errors. Select additional modules when you also want to prepare feedback or an assessment against your rubric.

Base: transcription and error analysis: 3 red pens for up to 2 pages. You receive the recognized text, a corrected version and marked errors with explanations.
Feedback: Optional +1 red pen: two lists covering strengths in the text and possible improvements.
Rubric assessment: Optional +1 red pen: suggested points for your criteria and a total score. Provide suitable criteria and maximum points.
Evaluation: Optional +1 red pen: a short overall response addressing the learner directly.

What to check before sharing the result

Check each relevant mark against the original. The results view shows AI suggestions; texts, marks and points cannot currently be edited or individually accepted or rejected there. PDF export uses the displayed AI result. Incorporate any necessary changes into your final feedback outside Tuba.

The upload accepts images of one submission. This workflow does not currently support pasting text, uploading a PDF or automatically separating a class set into individual submissions.

FAQ

The short answers first.

How much does correcting 25 submissions cost?

25 separate base corrections of up to 2 pages each use 75 red pens (3 per submission). With no existing balance, a pack of 90 red pens for a one-time payment of €24.00 covers this amount, leaving 15 red pens. Extra pages or modules increase usage. You buy whole packs; a calculated unit cost is not the purchase price. Upload different students' work separately.

Can I edit the AI correction before exporting it?

Can Tuba correct handwritten texts?

Yes. Tuba first reads photographed handwriting as text and then creates the correction. Clear photos and readable handwriting produce the most reliable results.

Do I need to type the text first?

No. You can photograph handwritten or typed pages. Tuba handles transcription and correction in one workflow.

Is Tuba only for teachers?

Tuba is built for classroom work and grading, but it also works for other texts where you want corrections to stay visible and explainable.

Does the AI decide the final grade?

No. Tuba can provide error analysis, feedback and grading suggestions. The final pedagogical decision stays with the teacher.

Correct a text, instead of retyping it.

Start with 12 free red pens — test real student writing before you buy anything.