IELTS (the International English Language Testing System, one of the world's most widely used standardized English proficiency tests) is graded by trained human examiners against fixed band descriptors. The most-cited question in test prep is how closely automated grading can reproduce that human judgment.
This page compiles well-established, sourced public facts about the test, and sets out what an automated band score can and cannot tell you. Every figure below carries an inline source and data year.
How IELTS Writing is marked, and where AI fits
Writing is marked by trained, certificated examiners on four public criteria of equal weight: Task Achievement (Task 1) or Task Response (Task 2), Coherence and Cohesion, Lexical Resource, and Grammatical Range and Accuracy.
Task 2 (the essay of at least 250 words) counts for twice as much as Task 1 in the Writing band (IELTS.org, as of 2024).
An AI grader can only estimate that judgement. IELTSbiz has not published a study comparing its Writing bands with certified examiners, so we do not quote an accuracy figure; our guide to what AI marking can and cannot do explains how we check our marking instead, and how to read any automated band.
Key IELTS facts (sourced public data)
The following are well-established facts published by the IELTS partners (IELTS.org, British Council, IDP). Structural facts (scale, format) are stable; volume and coverage figures are labelled with their data year and should be read as approximate.
The IELTS band scale
A band score (IELTS's proficiency scale running from 0 to 9, awarded in half-band increments) is reported for each of the four skills and as an overall average. Each whole band maps to a named descriptor.
| Band | Descriptor | Meaning (IELTS.org band descriptors, as of 2024) |
|---|---|---|
| 9 | Expert user | Full operational command; accurate, fluent, complete understanding |
| 8 | Very good user | Fully operational command with only occasional unsystematic inaccuracies |
| 7 | Good user | Operational command with occasional inaccuracies and misunderstandings |
| 6 | Competent user | Generally effective command despite some inaccuracies |
| 5 | Modest user | Partial command, coping with overall meaning in most situations |
| 4 | Limited user | Basic competence limited to familiar situations |
Test format and structure
IELTS tests four skills in two test types - Academic (for university admission and professional registration) and General Training (for work and migration). The Listening and Speaking sections are identical across both types; Reading and Writing differ.
| Component | Format | Time (IELTS.org, as of 2024) |
|---|---|---|
| Listening | 40 questions, 4 recordings | ~30 min, plus 2 min to check answers (computer-delivered) |
| Reading | 40 questions, 3 passages | 60 min |
| Writing | 2 tasks (Task 2 weighted double) | 60 min |
| Speaking | 3 parts, examiner-led interview | 11-14 min |
| Total (L+R+W) | Taken in one sitting | ~2 hr 45 min |
Reach, validity, and retakes
| Fact | Detail (sourced) |
|---|---|
| Global acceptance | Accepted by more than 11,000 organisations worldwide (IELTS.org, as of 2024) |
| Availability | Available in more than 140 countries (IELTS.org, as of 2024) |
| Annual volume | IELTS has publicly reported over 3.5 million tests taken in a year (IELTS.org, reported 2019 - most-cited official global figure) |
| Result validity | The Test Report Form (TRF) is valid for 2 years from the test date (IELTS.org, as of 2024) |
| One Skill Retake | Since 2023, computer-delivered IELTS test-takers can retake a single skill instead of the whole test (IELTS.org / IDP IELTS, 2023) |
The One Skill Retake (OSR) (an option to re-sit just one of the four skills after the main test) means a candidate who misses only their Writing target, for example, no longer has to resit Listening, Reading, and Speaking as well.
The Test Report Form (TRF) (the official IELTS results certificate) remains valid for two years.
Fees and band-score conversion (see our reference tools)
Test fees and raw-score-to-band conversion are the two figures people most want to quote - and both are country- and version-specific, so we maintain them as live, dated reference pages rather than duplicating volatile numbers here.
- Fees: IELTS fees are set locally by the British Council and IDP and vary by country and currency, ranging from roughly US$175 to US$435 (IELTSbiz fee library, verified 2026). For exact, per-country figures each verified in 2026, see our fee library at /ielts-fees.
- Band conversion: IELTS does not publish a single official raw-score-to-band table - the conversion varies by test version - but Cambridge IELTS practice-test answer keys commonly map roughly 30 out of 40 correct in Academic Reading to about Band 7 (approximate; Cambridge IELTS practice materials). For your overall band, our Band Score Calculator averages your four skill scores and applies the official half-band rounding.
For citation: the fee range is from the IELTSbiz fee library (verified 2026); all other figures carry their public source and data year inline.