Free plagiarism checker for PDF files
Upload a PDF, a Word document or a file from Google Drive, review its text, then check it for plagiarism and AI writing. Every match links to its source.
- PDF, Word, Google Docs, Sheets and Slides
- Nothing runs until you click Check
- Never used to train AI
Check the whole file, not a copy-paste
Copying text out of a PDF often breaks lines, drops tables and mixes up columns. Uploading the file reads the text in order.
You choose when it runs
Adding a file only reads it. You see the text and word count first, and no words are used until you start the check.
Plagiarism and AI in one report
Every match links to its source, and each sentence gets an AI likelihood. A likelihood is not proof, and any detector can flag writing a person wrote.
Straight from Google Drive
Pick a Google Doc, Sheet or Slides file, or a PDF or Word file stored in Drive. We only get access to the files you pick.
Files you can check for plagiarism
PDF and Word are the most common, but these all work in the Upload File tab.
| File | Extension | Good to know |
|---|---|---|
| PDFs with real text. A scanned page is a picture of text and can’t be read. | ||
| Word | .docx, .doc | The text of paragraphs and tables is read. Images are left out. |
| Plain text | .txt | Read as it is. |
| Rich text and OpenDocument | .rtf, .odt | From WordPad, LibreOffice or OpenOffice. |
| PowerPoint | .pptx | The text on every slide. |
| Excel | .xlsx | The text in the cells of every sheet. |
| Web page | .html | The visible text of a saved page. |
| Google Docs™, Sheets™ and Slides™ | From Google Drive™ | Picked straight from your Drive. Every tab of a sheet and every slide is read. |
How to check a PDF for plagiarism in 4 steps
Open the Upload File tab
Sign in to the web app (a free account is enough) and open Upload File in the editor.
Add your file
Drop a PDF or Word file in, choose one from your computer, or pick one from Google Drive.
Review the text
Nothing is checked yet. You see the file’s word count and any problem, such as a scanned PDF with no text.
Run the check
Click Use this text, choose plagiarism, AI detection or both, and run the scan. Several files on a paid plan? Click Check N files.
Writing in Google Docs? You can also check the document in place with the Google Docs add-on. Step-by-step help is in check for plagiarism in the web app.
File size and upload limits by plan
Uploading needs an account. Each check uses words from your plan, the same as pasted text.
| Plan | File size | Uploads | Several files | Words |
|---|---|---|---|---|
| Free account | 5 MB per file | 1 upload a day | One file at a time | 3,000 words a month |
| Student | 25 MB per file | 10 uploads a day | Up to 5 files at once | See pricing |
| Personal and Team | 25 MB per file | No daily limit | Up to 20 files at once | See pricing |
Google Drive imports count as uploads. Words per plan are on the pricing page.
When a PDF has no text to check
The checker reads the text inside a file. Some PDFs don’t have any.
Why a scanned PDF shows no text
A scan or a photo of a page is an image. The checker reads text, not pictures, so the file is marked “no readable text” in the list and skipped.
How to check it anyway
Export the original document from Word or Google Docs as a PDF or DOCX, or run the scan through a text-recognition (OCR) tool first, then upload the result.
Password-protected PDFs
Remove the password before you upload. A locked file can’t be opened, so it is marked in the list instead of being checked.
Paste a page of your PDF instead
Your first check is free without an account, up to 1,000 words. Plagiarism needs at least 30 words and AI detection at least 50.
A match is not always plagiarism
A quote in quotation marks with a citation can still show as a match. Open each linked source and decide what needs a citation.
Read how to interpret a plagiarism report, build missing references with the citation generator, or check only for AI writing with the AI detector.
More free writing tools
- Word counter Count words, sentences and paragraphs, with reading time.
- Character counter Count characters with and without spaces against common limits.
- Grammar checker Check grammar, spelling, punctuation and style in a whole text.
- Sentence checker Find and fix grammar, spelling and punctuation mistakes in a sentence.
- Essay checker Check an essay for grammar, plagiarism and AI writing.
- Punctuation checker Check commas, apostrophes, colons and quotation marks.
- Plagiarism checker Scan finished writing for copied or closely paraphrased text.
- AI detector See which sentences read as AI-written.
- AI detector for essays Check an essay for AI writing, sentence by sentence.
- ChatGPT checker See whether text reads as written by ChatGPT or another AI model.
- Paper checker Check a research or term paper for grammar, plagiarism and AI writing.
- Citation generator Build APA, MLA and Chicago citations for your sources.
PDF plagiarism checker questions
Check your PDF before you submit it
Upload a file or pick it from Google Drive. A free account includes 3,000 words every month.