By English Test Coach · Updated
Coherence and cohesion · checked 15 October 2026
How accurate are AI band scores for Coherence and cohesion?
Treat an AI band for Coherence and cohesion as a rough guide, not a measurement. AI checkers are good at spotting visible problems, such as missing paragraphs, overused linking words and repeated nouns, but less dependable at judging whether a whole argument moves forward logically, which is what separates band 6 from band 7 and above. None of the four checkers we read publishes an accuracy figure for this criterion alone, and neither do we.
Our own published test compared overall bands only: 24 of 27 official sample responses were estimated within one band, and responses officially marked 8 or above were read about a band low. This page explains what the criterion measures, compares the main ways to get it assessed and shows how to use an AI band sensibly.
What Coherence and cohesion measures
It is one of the four equally weighted criteria in the public IELTS Writing band descriptors, for Task 1 and Task 2 alike. In plain terms:
- Coherence is whether a reader can follow your ideas: a logical order, clear progression from start to finish, and paragraphs that each have one central topic.
- Cohesion is how the sentences connect: linking words that show the real relationship between ideas, and reference words such as “this”, “they” and “such” that point back without repeating nouns.
The bands differ in quality, not quantity. At band 7 linking is used flexibly with some over- or under-use; at band 6 it can be faulty or mechanical and a paragraph’s central topic is not always clear; at band 5 linking words are overused or inaccurate and paragraphing may be missing. Our plain-English guide to the descriptors sets out bands 5 to 8 in full.
The options compared for Coherence and cohesion
We read each provider’s own page on 15 October 2026 and report what it says about itself. We did not submit essays to other tools, so this is not a test of their accuracy.
| Option | How it judges the criterion | Strength | Limit | Published accuracy evidence |
|---|---|---|---|---|
| English Test Coach | Estimates a band for each of the four criteria and quotes the passages from your response behind each judgement. | You can check the quoted evidence for paragraphing, linking and referencing yourself instead of trusting a number. | The AI model often gave all four criteria the same raw band in our test records, and it reads very strong writing low. | Overall band only: 24 of 27 official sample responses within one band. No separate figure for this criterion. Our test record. |
| IELTS International AI essay checker | Says it analyses paragraph structure, logical flow and cohesive devices, and flags overused connectors (its checker page). | Describes checks that match the descriptors, including repeated ideas and new arguments in a conclusion. | No separate accuracy figure for Coherence and cohesion is given on the page. | Its page says estimates are “accurate within 0.5 bands of human examiners in the majority of cases”, without a figure for this criterion. |
| IELTS Writing Checker (ieltswritingchecker.com) | Says it “reviews progression, paragraph focus, referencing, and the way ideas and information connect” (its homepage). | The description covers referencing and paragraph focus, not just linking words. An optional paid expert review is offered. | No accuracy figure for Coherence and cohesion is given. | Its 2026 benchmark describes learner submissions and says it “is not a validated estimate of official examiner scoring” (benchmark). |
| WitPrep AI Writing Coach | Its guide rates AI performance on Coherence and cohesion as “High”, describing it as pattern-based detection of paragraphing and linkers (its guide). | Gives a band and a rationale for each criterion, according to the guide. | The guide describes detecting paragraphing and linkers rather than how the argument progresses, and gives no separate figure for this criterion. | Its figure of ±0.5 band 80–90% of the time for Writing comes from its own internal validation set of 3,200 essays (2024). |
| A human teacher or examiner | Reads the whole response as an argument and explains where the reader loses the thread. | Best placed to judge logical progression, unusual but effective structures and whether a link is accurate. | Costs money and takes time, and quality depends on the person’s training in the IELTS descriptors. | No published figure applies. Only the IELTS test itself gives an official score. |
| Self-assessment with the public descriptors | You compare your writing with the descriptors for bands 5 to 8. | Free, and it builds the judgement you need on test day. | It is hard to notice gaps in your own argument, and easy to mistake more linking words for better cohesion. | None. Use it alongside one of the other options. |
English Test Coach is our own product. Providers’ statements are theirs; an accuracy claim means most when it says what it was tested against.
What AI checkers see well, and what they can miss
- Paragraphing: usually reliable. A single block of text, a one-sentence paragraph or a missing conclusion is easy to detect. Whether the paragraph breaks follow the meaning is harder.
- Linking words: reliable to count, risky to reward. Software can count “Moreover”, “Furthermore” and “In addition” easily. The descriptors call overuse mechanical, so a checker that rewards more connectors pushes you the wrong way.
- Referencing and repetition: partly reliable. Repeated nouns and a vague “it” or “this” are easy to flag. Whether a reader would really be confused often depends on the whole argument.
- Topic sentences: partly reliable. A checker can see whether a paragraph opens by naming its point. Checking that every later sentence serves that point needs closer reading.
- Logical progression: least reliable. Whether each paragraph moves the argument forward, without sudden jumps or a conclusion that adds a new idea, is a judgement about meaning. An essay full of correct linking words can still go round in circles, and an unusual but clear structure can be marked down.
So an AI report is most useful when it points to specific sentences you can check, and least useful as a single number.
What our own test shows, and what it does not
We tested our checker on 27 IELTS writing responses published with an official band, and compared its overall band estimate with the official one.
- Overall accuracy: 24 of 27 estimates (89%) were within one band, with an average difference of 0.57 of a band and a largest difference of 1.5 bands.
- No figure for this criterion: the test compared overall bands only. We did not record an official Coherence and cohesion band for each response, so we cannot say how accurate our band for this criterion is on its own.
- Criteria that move together: in our test records the AI model often gave all four criteria the same raw band, such as 5 for each or 6 for each. Read our Coherence and cohesion band as part of the overall estimate, and rely on the quoted evidence for what to change.
- Strong writing reads low: four of the five responses officially marked 8 or 8.5 were estimated between 6.5 and 7.5. Every response officially marked 3 to 5.5 was estimated within one band.
The full method and limits are in our accuracy report.
How to use an AI Coherence and cohesion band
- Read the evidence, not just the band. Look at the sentences the report points to and decide whether you agree.
- Test your structure yourself. Write one sentence saying what each paragraph does. If those sentences do not read as an argument in order, fix the plan before the wording.
- Cut stacked connectors. Keep a linking word only where it shows a real relationship, such as contrast, cause or example, and use “this” or “such” to refer back.
- Compare several essays. A change across three or four reports is a better signal than one result.
- Add a human check when it matters. If a university or visa route depends on half a band, or you are aiming for 8, ask a qualified teacher. Our guide to AI checking or human correction compares the two.
Where English Test Coach fits
Our checker suits Academic and General Training candidates working towards a target of about band 5 to 7 who write regularly and want to see the evidence behind each criterion. Reports stay private, and the writing criteria lessons show what to practise next.
It is a weaker fit if you are already writing at band 8, where it tends to estimate low, or if you need an official score; no checker can give you one. Compare it with other tools in our checker comparison.
Questions about AI and Coherence and cohesion
Can an AI checker tell if I use too many linking words?
Usually, yes. Counting connectors such as “Moreover” and “Furthermore” is easy for software, and the public band descriptors treat overused or mechanical linking as a weakness. Check that the checker flags overuse rather than rewarding the number of linking words.
Why does my AI report give the same band for every criterion?
In our own test records the AI model often returned the same raw band for all four criteria, such as 6 for each. When that happens, the written evidence for Coherence and cohesion tells you more than the number.
Is an AI Coherence and cohesion band good enough for a visa or university decision?
No. Only the IELTS test gives an official score, marked by IELTS examiners. Use an AI band to decide what to practise, and if your plans depend on half a band, get feedback from a qualified human as well.
Do more linking words raise my Coherence and cohesion band?
Not by themselves. The descriptors reward links that show the real relationship between ideas, clear referencing and paragraphs with one central topic. A string of connectors at the start of every sentence is what band 6 calls mechanical.
How can I check the coherence of my own essay?
Write one short sentence saying what each paragraph does. If the sentences read as a logical argument in order, with no repeats and no jumps, your structure is probably sound. Then read each paragraph and check that every sentence serves its first sentence.
Does English Test Coach publish an accuracy figure for Coherence and cohesion?
No. Our published test compared each response's overall band with the official band, and we did not record a separate official band for each criterion. Overall, 24 of 27 estimates were within one band, with an average difference of 0.57 of a band.
See the evidence for your own writing
Write or paste a Task 1 or Task 2 response and get an estimated band for each criterion, with the passages behind each judgement.
Sources: IELTS Writing band descriptors (ielts.org), summarised in our own words; provider pages linked above, read on 15 October 2026; our test of 12 October 2026. English Test Coach is independent of IELTS, the British Council, IDP and Cambridge, and of every provider named here. An estimate from any checker is not an official IELTS score.