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Privacy

Privacy Policy

The short version: what you compare stays in your browser, we measure traffic without cookies, and ads are the only third party involved. Everything below explains how you can check that rather than take our word for it.

What you compare is never uploaded

Every comparison on this site is computed by JavaScript running in your own browser. The text you paste, the files you open, the images you load and the results they produce are held in the memory of your tab and nowhere else. They are not transmitted to us, not written to a database, not queued for processing, and not retained after you close the page.

There is no server-side component that could receive them. When you pick a file, the browser reads it locally through the standard File API — choosing a file is not uploading it. A share link encodes both inputs after the # in the URL, and browsers never send that part of a URL to any server, so the link carries a comparison that nobody has stored.

Because none of it exists on our side, there is nothing we could hand over in response to a request, and nothing to lose in a breach.

How to verify this yourself

You do not have to trust a policy page. Three checks, none of which takes long:

  • Watch the network. Open developer tools (F12, or Cmd+Option+I on a Mac), select the Network tab, and filter to Fetch/XHR. Clear the log, paste content into a tool, and let the comparison run. New entries should be limited to analytics and advertising requests; open any of them and read the payload. None contains what you pasted.
  • Pull the plug. Load any tool page, then switch your machine to airplane mode or disconnect the network. Paste two things and compare. It works — because the code doing the work is already on your device, and there is nothing left for it to call.
  • Read the code. Use View Source, or the Sources tab in developer tools, to read the JavaScript the page loaded. The comparison engines and the Web Worker files are shipped as-is. If a page were sending your content anywhere, there would have to be a request in that code that does it.

What we do collect

Aggregate traffic analytics, through Cloudflare Web Analytics. It is cookieless: it sets nothing on your device and builds no profile that follows you between sites. What it records is what a server log would show — page visited, referring site, rough country, browser and device class, page-load timings — reported as totals rather than individuals. We use it to see which tools people use and which pages load slowly.

There is also an event beacon built into the site, and it is currently switched off. If it is ever enabled, it would record a count of named events — for example that a comparison ran, or that an export button was pressed — together with the page it happened on. It has no field for your content and never will; it exists to count actions, not to describe them.

Advertising

Ads are served by Google AdSense. Google is an independent controller of what it collects through those slots and may use cookies or similar identifiers to select and measure ads, subject to your consent choice and its own policies. We send Google nothing you type into a tool, because we never have it.

In the EEA, the UK and Switzerland, and in United States regions covered by CCPA-style rules, ad serving runs behind a Google-certified consent management platform that asks for your choice before any personalised advertising or measurement takes place. Decline, and ads still appear, but they are non-personalised — selected from the page and general context rather than from a profile of you.

Your choice is stored on your device so you are not asked on every visit, and you can change it whenever you like. The "Privacy settings" link in the footer of any page reopens the consent dialog with your current selections shown. Save a different answer and it applies to the next page you load.

Outside the regions where the dialog is required, that link still lets you review what is set. Clearing site data resets the choice, and you will be asked again on your next visit.

What is stored in your browser

A small amount of local storage keeps the site usable between visits: your light or dark theme preference, and per-tool settings such as the view you last used, whether whitespace is ignored, or your preferred number of context lines. That data lives in your browser, is readable only by this site, and is never transmitted to us.

To clear it, use your browser's "Clear site data" or "Cookies and site data" control for diffviewer.com, or open developer tools, go to Application (or Storage) and clear Local Storage for this origin. The tools work perfectly well with all of it removed; you simply get the defaults back.

No accounts, and questions

There is no registration, no login, no profile and no email list. We hold no personal data about you, so there is no account to close and no export or deletion request to make — the usual mechanics have nothing here to operate on. Your consent record and local settings sit on your device, and the steps above remove them.

Questions about any of this are best sent through the feedback link on our about page. We would rather answer a specific question than have someone assume the worst.

Changes to this policy

If what we collect changes — a new analytics provider, the event beacon switched on, a different ad setup — this page is updated to say so as the change takes effect, and the summary at the top is revised to match. That your compared content stays in your browser is not a detail we intend to revisit; it is why the site is built this way.