IB Biology IA Grader

Grade your Biology IA before you submit. Upload your draft and get a mark for each criterion, comments tied to your sentences, and a list of what to fix first.

Grade my IASee what you get

5 free gradings a month. No card. Private to you.

Biology IA mark and criterion feedback in Marksy

91%

of Marksy's marks on Biology IAs land within one grade of the IB's final mark

Tested on 174 Biology IAs the IB had already marked. See how we tested

Marks
24, from four criteria worth 6 each
Length
3,000 words at most
Share of your grade
20%, at SL and HL
SL and HL
Same task, same criteria

See the mark, and the sentences behind it

Check the quality of your method, analysis, evaluation, communication and subject-specific reasoning. Find the weakest parts of the draft and see what to change first.

Biology IA: comments on your writing
Comments on your writingEach comment points at a passage in your draft, so you can see why Marksy said it.
Biology IA: what to fix first
What to fix firstA short list of edits in order, instead of changing random parts of the draft.

What Marksy checks for each Biology IA criterion

You get a mark for each IB assessment criterion below. The points under each one are what Marksy looks for in your draft. See the mark bands

Criterion A: Research Design

6 marks
  • The research question is focused and placed in a specific scientific context.
  • Method choices (variables, controls, range, repeats, data sufficiency) are explained, not just listed.
  • The procedure has enough detail for another student to reproduce it.

Criterion B: Data Analysis

6 marks
  • Raw and processed data are traceable, with units and uncertainties.
  • Calculations, graphs, and any statistics are correct and fit the research question.
  • Uncertainties are propagated or discussed where they matter.

Criterion C: Conclusion

6 marks
  • The answer to the research question is explicit and backed by your processed data.
  • The claim is no stronger than the evidence allows.
  • The result is compared with published values, theory, or other studies.

Criterion D: Evaluation

6 marks
  • Weaknesses are specific to this investigation, not generic.
  • The report explains how much each weakness affected the results.
  • Improvements are realistic and target the weaknesses you identified.

Where Biology IAs usually lose marks

Marksy flags these in your draft and links each one to the sentences it is about.

  • A question that is really a topic"How does temperature affect enzymes?" is a topic. Name the enzyme, the substrate, the range of values and what you will measure.Criterion A
  • Living material left uncontrolledSeeds, leaves, yeast and people all vary. Say how you kept samples alike (batch, size, age) and why your sample size is enough.Criterion A
  • Uncertainty that stops at the tableMany reports list ±0.5 °C and never use it again. Show how uncertainty or spread (standard deviation, error bars) affects the trend you describe.Criterion B
  • A statistical test with no reasonA t-test or correlation only helps if it answers your question. Say why you chose it and what the result means for your data.Criterion B
  • Claiming more than the data showsFive temperatures and three repeats rarely prove a cause. Make your claim only as strong as your evidence, and compare it with published findings.Criterion C
  • Weaknesses anyone could write"Human error" and "more repeats" earn little. Name the weakness that actually affected your results, say how much, and give a fix aimed at it.Criterion D

Before you upload

  • Include your raw data tables, not only the processed graphs.
  • Keep units and uncertainties in the table headings.
  • Show one full worked example of each calculation.
  • If you used a database or simulation, say where the data came from.

Your draft stays at the centre

Marksy reads the work you upload, points each comment back to your writing, and puts the most important changes first.

Can your research question be answered directly with the data you collect and process?
Read Biology IA Planning Guide
  1. 1

    Upload your draft

    A PDF of your Biology IA, finished or not. Every comment stays connected to your own writing.

  2. 2

    Read the comments

    Highlights show which passage each comment is about.

  3. 3

    Fix the important parts first

    Work down a short list instead of making scattered edits.

  4. 4

    Keep the final say

    Accept, adapt or ignore each suggestion. You stay the author.

What students wrote afterwards

From Trustpilot, as written.

marksyib has saved my ib diploma. thanks to it, my IA's were perfect and got the points i needed. really recommended.
maya balog, 13 February 2026
Marksy ib allowed me to be able to finish my IAs much before allowing me to be able to relax better. 100% recommended
Jordi Pasalaigua Peiron, 25 March 2026
Read the reviews on Trustpilot

Your work stays your work

Marksy reads the draft you upload and comments on it. It doesn't rewrite your assessment, and your files are never used to train AI.

Read the safety answers
  • Private to youOnly you can see your work unless you choose to share it.
  • Never used for trainingYour coursework is not added to any AI training data.
  • Feedback, not ghostwritingUse the report to improve your own analysis and decisions.
  • Delete it whenever you wantYou control the files stored in your account.

Questions before you upload

Still planning? The coursework guide covers the criteria and what to ask yourself while you write. Open the guide

It comments on whether your test fits your research question and whether you read the result correctly. If it flags a calculation, check it again in your spreadsheet.

Yes. Lab, field, database and simulation investigations use the same criteria. Marksy checks that your method explains how the data was chosen and why it is enough.

No. SL and HL students do the same scientific investigation and are marked against the same four criteria.

Yes. Up to three students can collect data together, but each of you writes your own Biology report. Upload your own report.

Along with the IB criteria, Marksy's science IA marking uses notes on how real IB-marked reports scored at each mark band. That helps it mark weak and strong reports more like an IB moderator would.

On 174 Biology IAs the IB had already marked, 91% of Marksy's marks landed within one grade. Across all 1,317 IAs and TOK essays we tested, it was 92%. On a set with as many weak as strong essays, it scored 74/100 on our marking score, against 65 for ChatGPT, 61 for Claude and 57 for Gemini. Every number, and how we tested, is on the grading accuracy page.

Yes. Marksy checks your Biology IA against the IB assessment criteria for it and returns marks, comments and fixes instead of generic essay advice.

Yes. Early drafts are useful because the report can show a weak criterion before you spend hours polishing the wrong section. You can revise and grade another version later.

A free account includes 5 gradings a month. You don't need a card.

No. Marksy reads your existing work, explains each comment, and suggests what to revise. The writing and the final decisions stay yours.

Your upload is private to your account, is not used to train AI models, and can be deleted whenever you want.

Stop guessing what to fix in your Biology IA

Upload the version you have now and find the parts holding it back.

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