Textumi vs Copyleaks: how the two AI detectors differ

Textumi and Copyleaks at a glance

Checked on 20.10.2026. Copyleaks' main website did not open for automated reading, so its facts come from its documentation and its Chrome Web Store listing; Textumi facts come from our product.

How each tool shows a result

Textumi places a needle on a gauge that runs from “Human” to “AI” and names the result with one of five labels, from “Human-written” to “AI-generated”. With an account you also see the passages that weighed most in the result. For a text under 50 words, it shows “Too little text to judge” instead of a label.

Copyleaks classifies each section of a text as either human or AI with a probability, and provides a summary of the whole text. The AI Logic feature highlights the sentences and phrases that read as AI-written in English, Spanish, French, Portuguese, German, and Italian. The level of sensitivity can be set at three levels.

A label and a percentage are both a model's estimate from the wording. Neither proves who wrote a text, and a percentage is not a measured share of generated text.

Which languages each detector covers

Textumi detects AI writing in 20 text languages. The English and Ukrainian detectors have the longest record. The detectors for the other languages were built and tested on a narrower set of texts, and some of them miss many AI texts in other genres, so a longer passage gives a steadier result there.

Copyleaks' documentation lists 30 languages for AI detection, among them French, Spanish, German, Polish and Ukrainian, and detects the language automatically. Its AI Logic explanations cover six of them.

Rewriting a draft: two different approaches

Textumi's Humanizer works in the same account as the detector. It rewrites a draft so that it reads more naturally and then checks the new version against your original: facts, names, numbers, exact names such as quoted labels, and the logic of each sentence. A version that fails these checks is not shown, and your original stays beside the result.

The Humanizer takes 50 to 2,000 words in English and up to 1,000 words in the other languages. It does not promise a lower score in any detector.

Copyleaks does not offer a humanizer or a paraphraser. Its documentation presents detection of heavily edited, spun and paraphrased text, and of manipulated characters, as part of its service.

Where you can use each tool

Textumi works in four places with one account. The web workspace takes pasted text, files and public web pages. Textumi for Chrome checks and rewrites text on any web page from a side panel. Textumi for macOS keeps the AI Detector and the Humanizer on a toolbar above your other apps and needs a Mac with Apple silicon. The MCP connector lets Claude, ChatGPT and other assistants check and rewrite a text with Textumi right in the conversation.

Textumi for Chrome

Copyleaks works on its website, in a Chrome extension and a Google Docs add-on, and through an API with libraries for several programming languages. Its official MCP server connects Claude, Codex, Gemini CLI, Cursor, VS Code and other tools, and its documentation says it needs a paid plan.

Both services connect to AI assistants through MCP. Textumi's connector also works with ChatGPT and starts Humanizer rewrites of English texts, and it is part of the MCP, Individual and Professional plans.

Privacy and history

Textumi stores submitted texts and results encrypted, and detection runs on Textumi's own servers. For rewriting, the text also goes to the external AI model provider named in our privacy policy. On Individual and Professional, your private History keeps requests for 30 days, and you can delete them earlier. A check without an account keeps no text.

Copyleaks' documentation describes encryption, SOC 2 and SOC 3 certification and an EU site with servers in Germany, and its API lets you set how long a scan is kept. For its full rules, read Copyleaks' privacy policy.

Who each tool suits

Copyleaks suits schools, publishers and companies that want AI and plagiarism detection in many languages, checks of source code, images or video, many file formats, or a detector built into their own systems through its API.

Textumi suits you if you want the detector and a Humanizer with fact checks in one account, a native app on your Mac, or checks and rewrites from inside your AI assistant. It also suits you if you want a check without an account, rewrites checked against your original, or a plain label with the passages behind it.

See Textumi plans

Sources and trademarks

Copyleaks is a trademark of its owner. Textumi is not affiliated with or endorsed by Copyleaks. Textumi wrote this comparison about its own product and a competitor from public information.