Privacy
A production trace carries your prompts, your users' messages and often your customers' data. This page states exactly what happens to it, and the answer is nothing.
Your trace never leaves your device
The file you drop or structured trace you paste — including a Claude Code session — is read inside this browser tab and analysed by JavaScript running on your machine. It is not uploaded, not streamed, not sampled, and not included in any error report. There is no server here that could receive it: the site is static files on a content delivery network, with no upload endpoint to send anything to.
Nothing is stored either. No cookies, no localStorage, no sessionStorage, no IndexedDB, no cache of your file or pasted text. Reloading the page loses the trace, deliberately — there is no "recent files" list because there is nothing to list.
The optional safe report is built locally from derived counts, dollar totals, confidence and recommendation labels. It excludes prompt text, response text, filenames, paths, session identifiers, tool names, tool arguments, tool results and trace fragments by construction; copying it uses your browser's clipboard and does not send it to us. Tool arguments and results are compared transiently to detect repeated signatures and prefix changes, then only aggregate counts reach the result.
You do not have to take our word for it. The analysis code ships unbundled and readable at /assets/engine/. Open your browser's network panel, drop or paste a trace, and watch: no request carries any part of it.
What we do collect
The site uses Umami, a cookieless analytics tool on infrastructure we run ourselves, to count page views and two events. It sets no cookies and builds no cross-site profile, and it honours your browser's Do Not Track setting.
Exactly two events exist, and they are frozen into a literal list in the code:
| Event | Sent when | Carries |
|---|---|---|
work_started | you drop a file, analyse pasted data or run the example | nothing |
work_completed | the analysis finishes | nothing |
Neither event carries any properties. Not the format we detected, not the provider, not the model, not the number of calls, not the token count, not the cost, not the file size, not the filename. Those are all facts about your trace, and the whole point of this site is that it does not learn them.
The gate is one short file — /assets/engine/analytics.js — and nothing else in the codebase touches the analytics provider. If a name is not in that list, it is refused before it reaches the network rather than sent and filtered afterwards.
Umami records the ordinary things a web server sees: the page URL, the referring page, a coarse country, and browser and device type. It uses the request IP address to derive location and an anonymous session, but does not store the IP address itself. We do not assign an account or other persistent identifier to you.
Why we process this information
Resend Cost's operator is the controller for this limited analytics data and for support email. We use aggregate analytics to learn whether the site and its core workflow are being used, and to find broken or abandoned journeys. For visitors in the EEA, UK and Switzerland, our lawful basis is our legitimate interest in operating and improving this free service, balanced by the safeguards described here: no cookies, no cross-site profile, no trace data, no event properties, and support for Do Not Track.
Self-hosted Umami keeps analytics records until we delete them; there is currently no shorter automatic retention period. The records are anonymous rather than connected to an account or email address. You can stop future analytics requests by enabling Do Not Track in a browser that exposes that setting.
No advertising, no payments, no accounts
There are no ads on this site and no advertising scripts of any kind. There is nothing to buy, so there is no payment processor. There are no accounts, so there is nothing to sign in to and no password to lose.
Because all analytics are cookieless and there is no advertising, no cookie consent banner is required and none is shown. We would rather not ask you to click something that changes nothing.
Third parties
- Amazon CloudFront and S3 serve the site's files. They see the ordinary request metadata any web host sees.
- Umami, self-hosted at
analytics.pagefabrica.com, receives the two events above.
That is the complete list. The vendor pricing pages are linked from About but nothing on this site fetches them at runtime, and no model provider is contacted at any point.
If you write to support@resendcost.com we keep your message and the address you used for as long as needed to answer and maintain the support record, or until you ask us to delete it where no legal obligation requires retention. This processing is necessary to respond to your request and is also in our legitimate interest in operating the service. Please do not send us a trace — we have no way to look at it that is more private than the one you already have, which is this page.
Your rights
There is no account to delete and no analytics profile that we can connect back to your name or email. If you have written to us, you may ask to access, correct or delete that correspondence, restrict or object to its processing, or receive a portable copy where applicable. You may also object to our legitimate-interest processing and complain to your local data-protection authority. Send any request to the address above; we may need enough information to locate the correspondence, but do not send a trace.
Last updated 14 August 2026.