Turnitin Draft Coach: Similarity, Citation, and Grammar Checks — The Official Limits

Draft Coach has three features with different quotas. Similarity checks are limited to three per assignment; citation checks and grammar checks are unlimited. Grammar uses US-English rules and only reports on the first 100,000 characters of a longer document. None of the checks add your draft to the Turnitin database, and instructors cannot see the checks themselves (our guide on whether teachers see Draft Coach covers that separately).

Turnitin's Draft Coach page describes three student capabilities:

"Address unintentional plagiarism early on — Students access similarity checks as they write in Word for the web and Google Docs to ensure proper paraphrasing, summarizing and other elements of authentic work prior to final submission."

"Improve citation skills — Using cutting-edge machine learning technology, Draft Coach helps students identify any missing references and citations."

"Correct grammar mistakes — Draft Coach highlights grammar errors and provides detailed explanations to guide editing."

The workspace is one sentence repeated across official pages: the checks run where you write — Word for the web and Google Docs. That is the whole product surface: it is not a standalone check for files saved elsewhere.

The official "How to use Turnitin Draft Coach" page states the quota directly:

"You will be able to run a total of three Similarity Checks while drafting your assignment. We suggest using these strategically to get as much out of the reports as possible."

The page's own advice is to spread them out rather than burn them early:

"Create a plan for using your reports prior to beginning your assignment... We strongly suggest that you make an effort to not use your checks all at once. Spread them out to help you improve your writing and citations over multiple drafts."

During the run, one rule matters: "Please do not alter your text while the Similarity Check is running. You can make changes as soon as the report has generated." And the result is framed as diagnostic, not verdict — "It is normal to receive some matches in a well-referenced paper and it doesn't always mean that it is plagiarism."

The most important line in the official page for cautious students:

"Running a Similarity Check will not add your assignment to our database so will not be used to match against your final paper."

A Draft Coach similarity check is a private run: your draft is not indexed against your final submission. The three checks are also your own — the instructor does not see them (see our guide on what teachers see). That is the difference between practicing in Draft Coach and submitting through the class inbox, which does enter the repository.

The other two checks carry no quota:

"You will be able to run as many Citation Checks as you like while you draft your assignment."

"You will be able to run as many Grammar Guide checks as you like while you draft your assignment."

Two limits do exist, both on grammar. The rules are US-English:

"Grammar Guide checks your draft using US-English grammar rules."

And the report caps at the first 100,000 characters of any document:

"For any particularly long documents, Grammar Guide will only provide a report for the first 100,000 characters. If your document exceeds this length and you would like to utilize Grammar Guide fully, we recommend splitting your draft into separate documents."

A thesis-length draft will exceed the cap; the official workaround is splitting the document, not submitting it whole and hoping the rest was checked.

After at least one similarity check, View Full Report opens an interactive version with two ways to read sources: Sources Overview shows top matching sources without overlapping matches; All Sources lists every match. The settings cog offers temporary exclusions — by search repository (internet, publications, submitted works) or by match type (bibliography, quotes, citations, small matches) — and the official page is explicit that these exclusions "do not save or pass back to Draft Coach." What you hide in the draft report stays hidden only there; it does not carry into the final similarity report of your real submission.

Draft Coach is three practice tools with three distinct quotas: three similarity checks per assignment (spread them), unlimited citation checks, and unlimited grammar checks under US-English rules with a 100,000-character cap. The checks run in Word for the web and Google Docs, they never add your draft to the turnitin database, and temporary exclusions stay in the draft view. Treat the three similarity checks as your only dry runs before the real submission — that quota is the scarce resource.