Zero-storage promise

Compression, grayscale, format conversion, watermarking and the rest of JustFileKit run entirely in your browser, and your files are never uploaded to any server. That is not a slogan; it is a fact about how the site is built, and you can check it.

Verify it yourself

  • Open the Network tab in your browser developer tools: while a file is being processed, no file content ever leaves the page.
  • The site has no server endpoint that receives file content.
  • Our Content Security Policy only permits the site's required services, analytics, advertising and error reporting; the processing code never sends file content to any of them.

What we store, and what we do not

  • Never stored: file content, file names, or processed results.
  • Stored: a free member's name, email, account identifier, preferred language, plan and update-consent timestamp. The tools remain free without signing in.
  • First-party stats: unidentified totals for page views, tool calls, file counts, bookmark clicks and share-button clicks are retained for 40 days. Only with your consent, a random visitor cookie lasts up to 90 days and estimates unique browsers that clicked bookmark or share using one-way codes. Deduplicated aggregates last 40 days. Signed-in accounts are counted separately across devices using one-way account codes. Visitor statistics contain no individual browsing history, IP addresses, emails, URL parameters or file names.
  • Only members who actively opt in receive product updates. You can opt out or delete all membership data from the account page.

How error reports protect you

To fix problems, the app reports the error message and stack trace when something breaks. Everything is scrubbed before it is sent:

  • Anything that looks like a file name (for example contract.pdf) is replaced with [filename] before sending.
  • URLs that could carry file content, such as blob: and data:, are stripped out.
  • No cookies, no request bodies, no email address, no identity information is sent, and there is no session replay.
  • These scrubbing rules are covered by automated tests, and the code is public so you can read it.

Traffic analytics and advertising

  • Google Analytics loads with storage denied by default. Before you allow analytics cookies, it sends only basic measurements without cookies. Use Cookie settings in the footer to change your choice and clear our visitor cookie. Existing deduplicated aggregates cannot be removed individually and expire under the retention period. The site may also use cookie-free Cloudflare Web Analytics.
  • The site may display ads through Google AdSense. Depending on consent, Google may use cookies or similar technologies to deliver, measure and personalize advertising.
  • Where required, Google's consent management platform lets you accept, reject or manage these choices. These services never receive the files you process.