Privacy
What data leaves your browser?
Reviewed by the Tabreon team · Last updated: September 2026
Quick answer
For a genuinely client-side tool, the content you're processing (your text, image, or file) never leaves your browser — but other data, like anonymous page-view analytics or account information, may still be transmitted separately.
Why this matters
A tool can be client-side for the specific operation you care about (like formatting JSON) while still sending unrelated data, like usage analytics — knowing the difference avoids both false confidence and unnecessary suspicion.
Definition
It helps to separate two categories: (1) the input data you're actively working with — the text, file, or content you paste or upload — and (2) incidental data a website may collect regardless, like anonymized analytics, cookies, or account details for features that genuinely require a server (such as a feedback form or login).
How it works
A tool built to process your input client-side never includes that input in any network request during the operation itself. Separately, the same website might still make network requests for unrelated purposes — loading the page, anonymous analytics pings, or submitting a different feature's form (like a feedback box) that legitimately needs a server. The way to verify this distinction for any specific tool is to check your browser's network activity while using it, or read the provider's privacy policy for an explicit statement.
Common mistakes
- Assuming an entire website is "fully private" because one specific tool on it processes data client-side — other pages or features on the same site may work differently.
- Confusing anonymized usage analytics (like a page-view count) with the actual content you're processing being transmitted.
Best practices
- Read a site's privacy policy for explicit statements about which specific features send data server-side and why.
- For maximum certainty, check your browser's network tab while using a sensitive tool — you should not see your input content in any outgoing request.