Privacylast updated 18 October 2026
Your text never leaves your browser
The AI detector runs on your own device. We don't receive, upload or store the text you check, and you can verify that yourself.
What runs where
| Step | Where it runs | Does your text leave the device? |
|---|---|---|
| Pasting or opening a .txt / .docx file | Your browser | No |
| Clean-up, sentence splitting, style counts | Your browser | No |
| Detection model | Your browser, in a background worker | No |
| JSON export and printing | Your browser | No (the file is created locally) |
What gets downloaded
Model and code downloads only go one way: from these hosts to your browser. The one exception is Google Analytics, which receives page views.
| Host | What | When |
|---|---|---|
| isthisaiwritten.com | The page, styles, scripts, the Cal Sans font and small data files (samples, benchmark results) | Every visit |
| cdn.jsdelivr.net | The open-source library that runs the model in the browser | First full check, then cached |
| huggingface.co and *.hf.co | The detection model files (about 131 MB), pinned to an exact version | First full check, then cached |
| openrouter.ai | On the home page only: OpenRouter's public list of AI model names, used to show the newest release of each model family. A plain request with no text, no cookies and no referrer; it is not part of any scan, so the scan's “bytes sent” meter leaves it out. | At most once a day, then cached in your browser |
| Google ad domains (googlesyndication.com, doubleclick.net and others) | Ads served by Google AdSense, on articles and guides only. Never on the home page, the scan workspace or any page with a text box. | Pages that show ads |
| googletagmanager.com and google-analytics.com | Google Analytics: which pages are visited, roughly from where, and on what kind of device. It never receives the text you check or your results, and it is paused while a scan runs. | Page views on isthisaiwritten.com |
On the home page and in the scan workspace, the page's Content Security Policy only allows network connections to the hosts above that serve the detector and analytics, so those pages can't send data anywhere else.
What stays on your device
- Model files, in your browser's cache, so later checks are fast and work offline. Remove them with “Delete downloaded models” under the detector, or by clearing this site's data in your browser settings.
- The list of newest model names, cached for a day in your browser's local storage so the home page fetches it at most once a day.
- Your text stays in the open tab only. We don't save it anywhere, on your device or ours.
- Exports you choose to download (JSON) are saved where your browser saves downloads, and nowhere else.
What we never collect
- The text you check, or any part of it.
- Your results.
- Anything from inside a scan. Google Analytics counts page views and sets its own cookies for that; it is paused while a scan runs and never sees your text or results.
- Accounts, emails or names: there is no sign-up. If you email us, we receive your address and your message and use them only to reply.
Our host
The site is served by Cloudflare Pages. Like any web host, Cloudflare processes standard request data, such as your IP address and browser type, to deliver the page and protect it from abuse. That data concerns the page request, not your text, which is never sent.
Analytics
We use Google Analytics to understand how the site is used: which pages are visited, how visitors arrive (for example from a search engine), roughly where they are (country or city, derived from the IP address) and what kind of device and browser they use. Google Analytics sets its own cookies (see Cookies) and processes this data on Google's servers, which may be in the United States. It never receives the text you check or your results, and it is paused while a scan runs.
You can opt out of Google Analytics on all websites with Google's opt-out browser add-on, or by blocking cookies for this site in your browser.
Advertising
Articles and guides on this site may show ads served by Google AdSense. Ads never appear on the home page, in the scan workspace or on any page with a text box, so ad code never runs where you paste text.
- Third-party vendors, including Google, use cookies to serve ads based on your prior visits to this website or other websites.
- Google's use of advertising cookies enables it and its partners to serve ads to you based on your visits to this site and/or other sites on the Internet.
- You can opt out of personalised advertising in Google's Ads Settings. You can also opt out of some third-party vendors' use of cookies for personalised advertising at aboutads.info.
- Learn more in How Google uses information from sites or apps that use its services.
Where the law requires it, for example for visitors in the European Economic Area, the United Kingdom and Switzerland, Google's consent message asks for your choice before ads cookies are used, and you can change it at any time from the link the message provides. If you decline, Google may still show non-personalised ads, which use cookies only for things like frequency capping and fraud prevention.
Who is responsible
IsThisAiWritten is run by Luis, its founder, from Switzerland. For any question about privacy or this policy, write to [email protected].
Your rights
Under the Swiss Federal Act on Data Protection, and the EU and UK GDPR where they apply, you can ask what personal data we hold about you, and ask us to correct or delete it, restrict or object to its use, or hand it over in a portable format. Where we rely on your consent, you can withdraw it at any time. We hold almost nothing that identifies you: analytics and advertising data are held by Google, and we will help you exercise your rights there too.
Write to [email protected] and we will reply within 30 days. You can also complain to a data protection authority: in Switzerland, the Federal Data Protection and Information Commissioner (FDPIC); in the EU or UK, the authority where you live.
Check it yourself
- Open developer tools (F12, or ⌥⌘I on a Mac) and choose the Network tab.
- Paste text and press Check for AI. On the first full check you'll see model files arrive from the hosts above.
- Search the requests for a word from your text. There are no matches.
- Set the Network tab to Offline and check again: once the model is cached, it still works.
Changes to this policy
When we change how the site handles data, we update this page and the date at the top. Earlier versions are available on request.