Direct answer
A single submission can check a paper for both plagiarism and AI writing at once: Turnitin generates a similarity report and, where the institution has it enabled, an AI writing report from the same upload [1][2]. The similarity figure is the share of your text that matches sources in the comparison database, while the AI indicator is the percentage of qualifying prose the model classifies as AI-generated; neither one is a verdict of misconduct on its own [1][2]. If you want to see both reports before you submit, a pre-submission scan returns the same two documents your instructor would open in their LMS.
Can One Scan Check a Paper for Both Plagiarism and AI Writing?
Yes. One upload produces both outputs because the two checks run on the same submitted file rather than on separate copies of your paper [2]. Turnitin's similarity report compares your text against its repository of student papers, publications, and internet sources, and the AI writing report is generated alongside it for institutions that have enabled that feature [2]. That is why students who scan once typically receive two PDFs rather than one.
It helps to be precise about what the similarity percentage means. It is not a plagiarism score in the legal or disciplinary sense; it is the proportion of your document that overlaps with matched sources, and those matches must be read in context [2]. A paper can show a high similarity figure purely because of a long reference list, a quoted block, or standard template wording that is correctly attributed.
The practical consequence is that you should never treat either number as a pass/fail gate. Read the match list behind the similarity figure and the flagged passages behind the AI figure, then decide what genuinely needs rewriting [2]. A single scan is a diagnostic, not a judgement.
What Do the Similarity Score and AI Score in a Turnitin Report Actually Mean?
The AI score is the proportion of qualifying prose in your document that the detection model classifies as AI-generated, not the probability that you cheated [3]. Turnitin only evaluates qualifying prose segments, so headings, short fragments, and reference lists are excluded from the calculation, which means the denominator is smaller than your total word count [1][3]. This is the single most common source of confusion when students compare their score against their own draft length.
Turnitin also suppresses low-confidence numbers. When the AI detection result falls below its 20% confidence threshold, the report displays an asterisk (%) instead of an exact percentage, signalling that the model cannot report a reliable figure [1][3]. A % is therefore a low-confidence signal, not a hidden high score.
Scores are also less stable on short or heavily edited text, because the model has less qualifying prose to work with and local revisions can shift the result [3]. That instability is exactly why institutions are advised to weigh the AI indicator alongside drafts, version history, and other evidence rather than acting on the number alone [3]. The similarity score deserves the same treatment: review the matched sources, check whether each one is properly quoted and cited, and only then judge whether the overlap is a problem [2].
How Can You Scan Your Paper Before You Submit It?
The most useful habit is to understand what the detector actually measures before you rely on it, because a score you cannot interpret will not help you revise [4]. Students who know that the AI indicator targets qualifying prose, and that similarity counts every match including correctly cited quotes, tend to read their reports far more accurately [1][4].
Once you have the report, revise rather than panic. Rewriting flagged passages in your own words and explaining the reasoning in your own voice both improves the writing and reduces spurious signals [4]. If a passage was genuinely drafted with ChatGPT, Claude, or Gemini and then lightly edited, that is the text most likely to be flagged, and it is the text that most benefits from a real rewrite [4].
Finally, keep your working evidence. Retaining drafts, notes, and version history lets you demonstrate authorship if a marker raises a question, and it turns a stressful conversation into a short one [4]. A pre-submission self-check is not about beating a detector; it is about catching accidental over-reliance on AI while you still have time to fix it [4].
If you would rather see the exact two reports your instructor will open — a similarity summary and an AI writing report from one upload — turnitin0 runs the scan before you submit, so your revision decisions are based on the real documents rather than a guess. Students use turnitin0 to preview both reports in minutes, then fix what actually needs fixing.
※ Turnitin0.com - Actual Turnitin AI Report Cover, Score, Flag And Similarity Summary
FAQ
Does one scan really cover both plagiarism and AI detection?
Yes. A single submission generates a similarity report and, where the feature is enabled, an AI writing report from the same file, so you do not need two separate uploads [2]. The two reports answer different questions about the same document.
Why does my AI score show an asterisk instead of a number?
Turnitin displays *% when the AI detection result falls below its 20% confidence threshold, meaning the model cannot report a reliable percentage [1][3]. Treat it as a low-confidence signal rather than a concealed high score.
Is a high similarity percentage automatically plagiarism?
No. The similarity figure is the share of your paper matching sources in the comparison database, and correctly quoted or cited material still counts as a match [2]. Only a contextual review of the match list tells you whether the overlap is a real problem.
What should I do if my paper is flagged for AI writing?
Rewrite the flagged passages in your own words and add your own reasoning, since light edits to AI-drafted text are the most likely to be flagged [4]. Keep your drafts and notes so you can show your working if a marker asks [4].
Can I see both reports before I submit my paper?
Yes — a pre-submission check returns the same two documents your instructor would open, so you can revise based on the real similarity summary and AI report rather than an estimate [1][2]. That is the point of scanning early: you still have time to act on what you see.