Plagiarism Checker — Real-Time, Honest, Free

Checks your sentences live against OpenAlex (250M+ scholarly works), Crossref (150M+ records) and Wikipedia — shows the exact source of every match. Nothing stored.

Quick answer: Free plagiarism checker that really works: checks your text in real time against 250M+ scholarly works, 150M+ Crossref records and Wikipedia. No signup, no upload — honest results.

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🌐 General-web mode — add your own free Google key (optional)

The default check runs against open scholarly + Wikipedia sources. To also scan the general web, create a free Google Programmable Search key (100 queries/day free) and paste it below. The key is stored only in your browser (localStorage) and is sent only to Google's official endpoint.

How to use

Paste your essay, article or report (about 40+ words).
Press Check — up to 12 key sentences are queried in real time.
Read the similarity %, inspect every match's source link, then cite what you missed.

About this tool

Most 'free plagiarism checker' pages run the same trick behind the curtain: they query a search index per sentence and show you matches. We do it in the open, against named public sources: OpenAlex (every scholarly work with an open record), Crossref (official DOI metadata) and Wikipedia. Every flagged sentence links to its source so you can verify it yourself. If a source is unreachable, we tell you instead of hiding it. That is what an honest originality check looks like — and your text never leaves your browser except as short search queries over HTTPS.

FAQ

Is this plagiarism checker really free?

Yes — no signup, no word limit on the page, no premium unlock. The check runs in your browser against free official APIs (OpenAlex, Crossref, Wikipedia).

Which sources does it check?

OpenAlex (250M+ scholarly works), Crossref (150M+ records with DOIs) and English Wikipedia (~7M articles), all queried in real time. Optional general-web mode uses your own free Google Programmable Search key, stored only in your browser.

How is the similarity percentage calculated?

We split your text into sentences, trigram-match each key sentence against source records, and divide the words in matched sentences by your total words. It is an honest arithmetic score — not a proprietary 'Turnitin-style' index, and we never claim otherwise.

Is my text uploaded or stored?

Your text stays in your browser. Only short search-query versions of checked sentences are sent over HTTPS to the source APIs. Nothing is saved on our side; session results cache in your own browser only.

Why didn't it find a match that Turnitin finds?

Turnitin matches paywalled journals and a private student-paper database. We check named open sources only and say so plainly — we will not fake a bigger corpus than we actually search.

How do I lower my similarity score honestly?

Quote with citation marks, paraphrase properly, and add a reference for every source you used — then re-check here. Pair it with our paraphrasing tool and citation generator.

Does it work on mobile?

Yes — it is a normal web page, works on iPhone and Android with nothing to install.

Rate this tool

Your rating stays in this browser (local storage) — nothing is sent to any server.

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🔢

The complete plagiarism checker guide

Prefer the long version — a worked example, the mistakes people actually make, and answers to real questions? The blog guide Plagiarism Checker — Complete Guide, Mistakes & FAQ covers all of it step by step.

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Plagiarism Checker — Real-Time, Honest, Free

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About this tool

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