Plagiarism Checker Free — No Signup
The fastest way to check a piece of writing for duplicate content without creating an account. Everything runs in your browser, so your work stays private. Get 3 free web checks per day as a guest, more when logged in.
Last updated: 2026-08-11 · Privacy
Why a no-signup plagiarism checker?
Most plagiarism tools force you to register, upload your work to their server, and then wait. That is slow and, frankly, a privacy risk when the document is a draft, an exam answer, or an unpublished article.
CopyCheck Online runs the core comparison locally with shingle fingerprinting. No registration for the free tier, no upload, no waiting for a server — results in milliseconds.
By the numbers
- 1Guests: 3 free web-search checks per day, no account.
- 2Logged-in users: 10 free web checks per day.
- 3Local corpus check: unlimited, fully offline, instant.
- 40 documents stored on our servers for local checks.
- 5Supports TXT, MD and PDF upload up to 10,000 chars.
Free vs paid web check
| Free Check | Web Deep-Check (credits) | |
|---|---|---|
| Login required | No | Yes |
| Searches live web | Yes (daily quota) | Yes + full crawl |
| Max chars | 5,000 (free tier) | 15,000–30,000 |
| History | 7 days | Lifetime |
| AI rewrite | Limited | Full access |
Check in 20 seconds
- 1Open the homepage
No signup needed — the checker is right there.
- 2Paste or upload
Paste up to 10,000 chars or drop a TXT/MD/PDF file.
- 3Press Free Check
Local corpus match runs instantly; tap Login for Web Check to compare against live pages.
Try it: paste this and hit Free Check
Content marketing is a strategic approach focused on creating and distributing valuable content to attract a clearly defined audience.
Similarity 71% · Match found on marketing.example.com · Match found on seo-guide.example.org Grade: C — 2 passages need rewriting
FAQ
Do I really not need an account?
Correct. The Free Check works for guests (3 web searches/day). Logging in just raises the quota to 10/day and unlocks history.
Is "free" really free, no credit card?
Yes, no credit card. Credits are optional and only for the deep web-crawl tier.
What happens to my pasted text?
Local checks never leave your browser. Web checks send only a short search query (a few hundred chars), never the full document.
Sources
- · Free tier policy: 3/day guests, 10/day logged-in (server-enforced, app/api/uapi/search/route.ts)
- · Local engine: shingle fingerprinting + FNV-1a + Jaccard (browser-side)
- · Web search providers: Tavily Search API, UAPI aggregate search