Turnitin Filters and Settings: How They Change Your Score
Turnitin's filters and settings decide which matches count towards your similarity score. Instructors can exclude quotes, the bibliography, small matches and specific sources, and control repository storage, resubmissions and report visibility. The same paper can score 35% with no filters and 8% with them. Here is what each filter does and how it changes your score.
Similarity report filters
| Filter | What it does | Effect on score |
|---|---|---|
| Exclude bibliography | Ignores matches in your reference list | Often a big drop |
| Exclude quotes | Ignores text in quotation marks | Drop if you quote a lot |
| Exclude small matches | Ignores matches under a word count or percentage | Removes common phrases |
| Exclude sources | Removes chosen sources, such as your own earlier submission | Targeted drop |
| Exclude abstract and methods (some versions) | Ignores standard sections | Useful for research papers |
In the newer report view, matches are also grouped into Not Cited or Quoted, Missing Quotations, Missing Citation, and Cited and Quoted. See Match Overview and how to read a report.
Assignment settings your instructor controls
- Repository: store papers in the standard repository, an institution repository, or not at all.
- Resubmissions: allowed or not before the due date. After three, new reports wait 24 hours.
- Student view: whether you see the similarity report, and when.
- Search targets: internet, publications and student papers.
- AI writing detection: on or off; usually visible to instructors only.
How to use Turnitin similarity with filters
- Open the report and find the filter or settings icon.
- Tick "exclude bibliography" and "exclude quotes" to see the score without them.
- Set a small-match threshold, for example 10 words.
- Check the remaining matches; these are the ones to fix.
Students can only change filters if the instructor allows it. What score is fine? See acceptable similarity percentage.
Filters do not change the AI score
The AI writing report has no exclude filters. If AI writing is flagged, the text itself has to change:
Check your paper with Turnitin's standard settings for $3.99, with both reports included.
Frequently asked questions
What do Turnitin filters do?
They remove chosen matches from the similarity score, such as the bibliography, quoted text, small matches or specific sources.
Can students change Turnitin filters?
Only if the instructor allows it.
Do filters change the AI score?
No. The AI writing report has no exclude filters.