Privacy

Your JSON is read and parsed by your own browser. It is never uploaded, and there is no server that could receive it — the whole app is static files.

That is the short version. Below is every case where anything at all leaves your machine, because “we never see your data” is worth nothing if the exceptions are hidden.

Three things that do leave your browser

  1. Anonymous page analytics. We use Plausible, which sets no cookies and records no personal identifiers. It logs the page you viewed and seven interaction events — whether a parse succeeded or failed, whether a file was over 50MB, and whether repair, query or share was used. It never receives your JSON, your filenames, or anything from inside your document. You can turn it off with the switch in AI key settings, and we honour Do Not Track and Global Privacy Control automatically.
  2. Loading JSON from a URL. If you paste a web address into the URL box, your browser fetches it directly from that host. We do not proxy it and never see the address or the response. That host will see your IP, as it would for any request you make.
  3. The Explain feature. This is the only case where part of your document is sent somewhere. If you add your own API key and click Explain, the value you selected is sent from your browser to api.openai.com or api.anthropic.com, whichever you chose, under your own account and their terms. Nothing is sent unless you set up a key and click the button.

Share links put your JSON in the URL

The Share button compresses the document into the link itself, after the #. Browsers never send that part to a server, so we still do not receive it — but anyone you send the link to has the whole document, and it will sit in their history. Treat a share link as a copy of the data, not a reference to it.

What is stored on your device

All of this is in your browser’s local storage, readable only by this site on this device, and cleared when you clear site data.

json-tool:autosave:v1
The document you last had open, so a refresh does not lose it.
json-tool:theme
Light or dark.
json-tool:editor-pane-split:v1
Where you dragged the divider.
json-tool:query-history
Recent queries, for the up-arrow recall in the Query tab.
json-tool:ai-config:v1
Your AI provider choice and API key, if you set one up.
json-tool:ai-privacy-ack:v1
That you have seen the AI disclosure.
json-tool:ai-daily-count:v1
A local counter so the AI feature can cap its own spend.
json-tool:analytics-opt-out
Set when you opt out of analytics.

One of those deserves a warning: json-tool:ai-config:v1 holds your API key in plain text. That is normal for a browser-only tool — there is nowhere safe to put a secret in a page that has no backend, and encrypting it locally would only move the key next to the lock. Anything with script access to this origin could read it. Use a key with a spending cap, and delete it from AI key settings when you are done.

No accounts, no tracking, no sale of anything

There is nothing to sign up for, so there is no account, no email address, and no profile. There are no third-party trackers, ad networks or session recorders. We have no data to sell and no mechanism to sell it.

Questions

This page describes the app as it is built today. If something here does not match what you observe, that is a bug worth reporting — open your browser’s network tab and check us.

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