Free OET Writing Mistakes Finder
Catch the OET writing mistakes that most often drop candidates from Grade B to Grade C — irrelevant content, weak openings, wrong register, missed purpose, and conciseness issues. Free, instant, no signup.
A free tool from the OET writing correction service — human expert corrections available from $15 when you need a full grade.
How to use the OET Mistakes Finder
Step 1
Paste your letter
Drop your full OET letter into the input.
Step 2
Run the scan
The tool flags the 8 most common OET writing mistakes with a brief explanation each.
Step 3
Prioritise
Focus first on Purpose and Content errors — these have the biggest band-score impact.
Step 4
Rewrite
Rewrite the flagged sentences and re-run.
Frequently asked questions
What are the most common OET writing mistakes?+
Missing the letter's purpose in the first paragraph; copying irrelevant case-note information; using informal register; flat openings; sign-off mismatches; and over-long sentences that hurt Conciseness.
Will fixing these get me to band 350?+
Fixing the top-3 patterns is usually enough to move a 300-band letter to a 350-band letter. The Mistakes Finder shows you which patterns to fix first.
Does this replace expert educator correction?+
No. For a Grade B target letter, pair AI feedback with at least one expert educator correction from our paid service.
Is the feedback aligned with the 2026 criteria?+
Yes. The mistakes-finder uses the six current criteria with 2026 strictness conventions.
This tool was designed by Dr. Mariam, PhD (English Professor, 20+ years of OET and IELTS teaching, 11,000+ letters personally marked). OET is owned by Cambridge Boxhill Language Assessment (CBLA). This tool is independent of CBLA and is not an official OET product. Target keyword: oet writing mistakes finder.
Want an expert's eyes on your OET letters? Dr Mariam's OET writing correction service marks every letter against all six OET writing criteria and returns line-by-line corrections within 24–72 hours.
See how it works