Originality.ai

Originality.ai checks written content before it goes live. Paste text, upload a file, scan a URL or run a whole site, and it scores how likely the text is to be AI-written, checks it for plagiarism, flags factual claims that may be wrong, and gives grammar and readability scores. A Chrome extension can replay how a Google Doc was written, keystroke by keystroke, which helps when you need to show a writer actually wrote it.

Pick it if you pay freelancers or an agency for content and want to know what you're getting, or if you run an SEO site and want to check pages at scale. It is aimed at publishers, agencies and marketers, unlike GPTZero and Turnitin, which focus on schools. Grammarly and QuillBot have AI checkers built in, but Originality.ai's is stricter and comes with bulk scans, team accounts and an API.

The catch: no AI detector is reliable enough to be proof. Independent tests put its false-positive rate at around 5% or higher, well above the vendor's claim, and writers regularly complain about being wrongly flagged with no way to appeal. Use the score to start a conversation with a writer, not to end one.

• Content agencies
• Publishers
• SEO teams
• Marketing managers
• Website buyers

Publishers, content agencies, SEO teams and businesses that commission written content and want to check it before publishing.

• AI detection

  Scores how likely text is to be AI-written, highlighted sentence by sentence, with a choice of stricter or more lenient models.

• Plagiarism checker

  Compares content against the web and shows matching sources.

• Fact checker

  Flags claims in an article that may be wrong or made up, with sources to check against.

• Bulk and site scans

  Scan many documents or a whole website at once to find AI or copied pages.

• Writing replay

  Chrome extension replays how a Google Doc was written, to show whether it was typed or pasted.

• API

  Plug checks into your CMS or content workflow (Enterprise plan).

• Free

  Free

  Checking the odd article.

  • A small free word allowance
  • AI, plagiarism, grammar, readability and fact checks
• Our pick

  Pro

  $14.95/mo, or $12.95/mo billed yearly

  Agencies and site owners checking content every week.

  • 200,000 words of scanning a month
  • Bulk and deep scans
  • File uploads and shareable reports
  • Team management

• Enterprise

  $179/mo, or $136.58/mo billed yearly

  Publishers and large content teams.

  • 1.5 million words a month
  • API access
  • Priority support and a year of scan history

Prices in USD unless noted, checked 22 October 2026. Vendors change plans often, so confirm on their site before you buy.

Ways Originality.ai can slot into your week.

1. 1

   Screen freelance content

   Run every commissioned article through AI and plagiarism checks before you pay the invoice.

2. 2

   Audit your site

   Scan your existing blog to find thin AI pages or copied content that could hurt search rankings.

3. 3

   Fact-check before publishing

   Flag shaky claims in a draft so an editor can check them against sources.

4. 4

   Due diligence on a website purchase

   Check how much of a site you're buying was written by AI or copied.

It sits between writing and publishing: drafts come from writers or AI tools, Originality.ai checks them, then they go into WordPress or your CMS. Pair it with Surfer or Clearscope for SEO optimisation.

The closest alternatives to Originality.ai in the library, best rated first.

• 

  Grammarly

  4.3

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  DeepL

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  QuillBot

  4.1

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• 

  Sudowrite

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