How Long Does a Turnitin Similarity Report Take? Processing Time, Pending States, and What Actually Means Trouble

Turnitin's official student guidance says Similarity Reports are usually generated within 10 to 15 minutes of submission, and that extreme usage during a particular academic year, or the submission of a very large file, can change the generation time. A resubmitted or overwritten file can take up to 24 hours to generate a new report. If the submission tile instead shows "Processing", "Available after [due date]", or "Processing failed" — each state means something different, and only some of them need you to do anything.

The official "Opening the Similarity Report" page states the standard window directly:

"Similarity Reports are usually generated within 10 to 15 minutes of submission."

And documents the exceptions:

"Depending on extreme usage that may occur during a particular academic year, or because of the submission of a very large file, report generation time may vary."

Turnitin's troubleshooting page for loading delays repeats the same numbers and adds the resubmission case:

"Uploaded files can take up to 10-15 minutes to process and generate a Similarity Report."

"Overwritten or resubmitted files may take up to 24 hours to generate a new Similarity Report to allow resubmissions to correctly process without matching to the previous draft."

So 10-15 minutes is the documented baseline, not a guarantee; extreme usage and large files move the window; resubmission has its own 24-hour rule.

The resubmission timing is documented on Turnitin's report-generation page:

"You are allowed three resubmission attempts where the Similarity Report will generate immediately."

"After three attempts, you'll have to wait 24 hours before a new Similarity Report can be generated."

"Resubmission attempts are shared between you and your instructor. If they attempt to resubmit on your behalf one of your attempts will be used."

This is the same rule that appears in the student self-check guidance (Draft Coach / resubmission path): first three attempts generate immediately, fourth onward waits 24 hours. A "report still generating" moment after many resubmissions is often the resubmission clock working, not the system being slow.

Turnitin's student guidance describes the three non-numeric states a submission tile can show:

• Processing: Turnitin has not finished comparing your submission yet — check back in a few minutes.
• Available after [due date]: you will only see the report after the listed date (the assignment due date) — this is the instructor's report-generation setting, not a delay.
• Processing failed / time-out: Turnitin ran into a problem generating the report — screenshot it and tell your instructor via email.

The "Available after [due date]" state is worth calling out separately because it is not a processing delay at all: the instructor set the assignment to generate Similarity Reports on the due date. The report is not stuck — it was never supposed to exist before that date.

Turnitin's troubleshooting page for loading delays lists the common failure reasons:

"Files containing dense vector images: This can cause the file to take too long, or fail, to process. Replace any vector images (AI, EPS, WMF, and PICT) in the file with raster images (jpg/jpeg, psd, png, tiff, bmp and gif) and try submitting again."

"The first page includes an image and no text: This can cause the file to fail to process, which makes the report inaccessible. Modify the first page of the file to include text and try submitting again."

"PDF from a third-party PDF converter: Use trusted sources such as Adobe, MSOffice365, or Google Docs for PDF creation."

"The file is password protected: Remove password protection and resubmit the file."

The same page names the error codes you might see:

"The M14:11 error code is usually accompanied by the message 'Your Session Has Expired. This paper is not available.'"

"Alternatively, the Similarity Report may appear to load but displays the message 'Oops! There was an issue loading your Similarity Report. Please check again later.'"

These are file-side problems with a documented fix — not a queue you wait out.

From the same official pages, the line between "wait" and "act" is:

• Wait: a dash or "Processing" within the 10-15 minute window; "Available after [due date]" — the report was set to generate later by the instructor.
• Act: "Processing failed" or "Time-out" state — screenshot it and email your instructor; a report that never appears after the documented windows and after you have checked the file-side causes — contact your instructor or Turnitin administrator.
• Fix yourself first: file-side causes (dense vector images, image-only first page, third-party PDF, password protection) have documented fixes — fix the file, resubmit, and only then escalate.

The documented 24-hour cap for resubmissions also means: if you need a report before your deadline, plan the resubmissions so the clock works for you, not against you.

Turnitin's own pages set the expectations: Similarity Reports usually generate within 10-15 minutes of submission; extreme usage or a very large file changes the window; resubmitted files can take up to 24 hours. The states on the submission tile each mean something specific — Processing is a wait, "Available after [due date]" is an instructor setting, Processing failed needs a screenshot to your instructor. Most "report missing" moments are either the documented windows or file-side problems with documented fixes. Understanding which state you are in is the difference between waiting calmly and escalating correctly.