Free Plagiarism Checker
Check up to 1,000 words for plagiarism against Google, with highlighted matches, source links, a uniqueness score and CSV export.
Check your text for plagiarism
Paste up to 1,000 words. We search Google for your most distinctive sentences and show you every page that contains them.
0 / 1,000 words
Your text
Found online Unique
Matching sources
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Quick answer
A plagiarism checker compares your writing with content already published online and shows you any sentences that appear elsewhere. This free tool searches Google for your most distinctive sentences as exact phrases, highlights any matches, lists the pages they came from, and gives you a clear uniqueness score.
What is a plagiarism checker?
A plagiarism checker is a tool that scans a piece of text and looks for the same wording on other websites. If a sentence in your article already exists on another page, the checker flags it so you can rewrite it, quote it properly or add a citation. Writers, editors, marketers, students and website owners all use a plagiarism checker to make sure their content is original before it goes live.
Original content matters for two reasons. Readers trust writing that feels fresh and personal, and search engines prefer to rank the original source of an idea. When the same paragraphs appear on several websites, Google normally picks one version to show and filters out the rest. Checking your text first keeps your page in the strongest possible position.
The Rank Shifters plagiarism checker is free, needs no signup, and checks up to 1,000 words at a time. It works directly in your browser, so you can paste a draft, run the check, and read your report in under a minute.
How to use this free plagiarism checker
1. Paste your text
Copy your article, blog post, product description, essay or web page copy and paste it into the box above. The counter below the box shows how many words you have used out of the 1,000 word limit. For longer pieces, check them in sections.
2. Ignore your own website (optional)
If the text is already published on your site, type your domain into the Ignore matches from my website box. The plagiarism checker will then leave your own pages out of the results, so you only see copies on other websites. This is the fastest way to find sites that have copied your content.
3. Run the check
Click Check plagiarism. The tool splits your text into sentences, selects up to 25 distinctive ones spread evenly through the piece, and searches Google for each one as an exact phrase. A progress bar fills as results arrive, and each sentence is coloured as soon as it has been checked.
4. Review your report
The summary strip shows your uniqueness score, how many sentences were checked, how many were found online and how many matching sources there are. Highlighted sentences in your text are the ones that appear elsewhere. The sources table lists every matching page with a link, so you can open it and compare the wording. Use Copy report or Download CSV to save the results or share them with your team.
How this plagiarism checker works
Most online plagiarism tools work in a similar way to a search engine: they break text into pieces and look for those pieces in a large index of web pages. This tool uses the largest index of all, Google, through a live search API.
- Sentence splitting: your text is divided into sentences at full stops, question marks, exclamation marks and line breaks.
- Smart sampling: very short lines such as headings are skipped because they match almost everywhere. Up to 25 sentences of 8 words or more are chosen evenly from the start, middle and end of your text.
- Exact phrase search: each sentence is searched in quotation marks, which tells Google to return only pages that contain those exact words in that exact order.
- Scoring: the uniqueness score is the share of checked words that were not found on any other page. Longer matched sentences lower the score more than short ones.
Your full text is never stored. Only the individual sentences are searched, and their results are kept for a short time so that repeat checks of the same text stay quick.
What is a good uniqueness score?
| Score | What it means | Suggested action |
|---|---|---|
| 90–100% | Highly original | Ready to publish. Review any single highlighted sentence. |
| 70–89% | Mostly original | Rewrite or cite the highlighted sentences before publishing. |
| 0–69% | Significant overlap | Rework the piece in your own words and add original insight. |
A few matches are completely normal. Common phrases, standard definitions, product specifications and quotes will often appear on other pages. The goal is not a perfect 100% every time, it is making sure the substance of your content is your own.
Why original content matters for SEO
Search engines want to show people a variety of useful results, not the same paragraph ten times. When Google finds identical text on several sites, it usually chooses one page as the original and shows that page in the results. Original content gives your page the best chance to be that chosen result.
- Better rankings: unique, helpful content is one of the clearest signals of quality and matches what Google describes as people-first content.
- More backlinks: other writers link to original research, fresh ideas and clear explanations. Copied content rarely earns links, which is why original content and link building services work so well together.
- Stronger brand trust: readers notice when writing feels generic. A distinct voice keeps them reading and coming back.
- Safer guest posts: publishers check submissions for originality. Running every article through a plagiarism checker before you pitch keeps your guest posting placements approved quickly.
Who uses a plagiarism checker?
Content writers and bloggers
Writers use a plagiarism checker to confirm that research notes have been fully rewritten and that no copied sentence has slipped into the final draft.
Editors and content managers
Editors check freelance submissions before they publish, which protects the site’s reputation and search visibility.
SEO teams and agencies
SEO teams check service pages, product descriptions and outreach articles. Clean, original copy is the foundation for every link building and content campaign.
Website owners
Site owners paste their own published paragraphs, ignore their domain, and see whether any other website has copied their work. If a site has copied you, you can contact the owner, ask for credit and a link, or file a removal request.
Students and teachers
Students check essays for accidental copying before they submit, and teachers can spot passages taken from public websites.
How to fix plagiarism in your content
- Rewrite in your own words: read the source, close it, then explain the idea the way you would to a friend.
- Add a citation: when you use a fact, statistic or idea from another source, name it and link to it.
- Use quotation marks: when the exact wording matters, quote it and credit the author.
- Add original value: include your own examples, data, screenshots or experience. These make content unique and far more useful.
- Check again: run the plagiarism checker one more time after your edits to confirm the highlighted sentences are clear.
Plagiarism vs duplicate content
The two terms are close but not identical. Plagiarism means using someone else’s words or ideas without credit. Duplicate content is an SEO term for blocks of text that appear at more than one address, which can happen on your own site through printer pages, URL parameters or copied product descriptions. This tool finds copies across the wider web. To compare two of your own pages side by side, use our duplicate content checker.
What this tool can and cannot check
The plagiarism checker searches public web pages that Google has indexed. That includes blogs, news sites, business websites, forums and most online publications. Because it relies on public search results, it cannot see private student paper databases, paywalled journals, offline books or pages that block search engines. Very new pages may also take a few days to appear in Google before they can be matched.
Frequently asked questions
Is this plagiarism checker free?
Yes. The Rank Shifters plagiarism checker is completely free, with no signup and no credit card. You can check up to 1,000 words per run.
How does the plagiarism checker work?
The tool splits your text into sentences, picks the most distinctive ones, and searches Google for each as an exact phrase. Any public page that contains the same sentence is listed as a matching source, and the sentence is highlighted in your text.
What does the uniqueness score mean?
It is the share of the checked words that were not found anywhere else online. A score of 100% means none of the checked sentences appeared on another indexed page.
What is a good uniqueness score?
For blog posts, service pages and web copy, aim for 90% or higher. Short common phrases, quotes and standard definitions can match naturally, so review each highlighted sentence rather than chasing a perfect number.
Can I check my own published content?
Yes. Enter your domain in the "Ignore matches from my website" box and the tool will leave out your own pages, so you only see copies on other websites.
How many words can I check?
Up to 1,000 words per check. For longer articles, check the piece in sections.
Does it check every sentence?
It checks up to 25 sentences spread evenly across your text, skipping very short lines that would match almost anywhere. That sample gives a reliable picture of the whole piece.
What sources does it compare against?
It compares against public web pages indexed by Google, which covers blogs, news sites, business websites and most online publications.
Can it check academic papers or private databases?
No. It searches the public web through Google, so it cannot see private student paper databases, paywalled journals or offline books.
Is my text saved or shared?
Your full text is never stored. Only the individual sentences are searched, and their results are cached briefly so repeat checks stay fast.
Why is duplicate content a problem for SEO?
When the same text appears on several sites, Google usually shows only one version. Original content gives your page the best chance to rank, earn links and build trust with readers.
Can I use this to find sites copying my content?
Yes. Paste a few paragraphs from your own page, add your domain to the ignore box, and any other site using your text will appear in the sources table.
Is there a limit on how often I can use it?
Each visitor can run around six full checks per hour, which keeps the tool fast and free for everyone.
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