Check a receipt
A GUARDIANA ZERO receipt is the proof of what they tried to take from your browser. Here you can check that nobody has touched it.
What a receipt is, in plain words
- 1You browse with GUARDIANA ZERO
Every time a page tries to send something to a tracking or advertising company or a data broker, ZERO cuts it before it leaves and writes it down: the time, the page you were on, the company, its country and what the request carried (by the names of its fields: «the page you are on», «an identifier of yours», «your screen size»…). It never writes down the values: your data is not written anywhere.
- 2You ask for the receipt
In «What was cut», the «Signed receipt» button saves that list to a file (.json) in your Downloads folder. The file is yours and never leaves your computer.
- 3ZERO seals it
When saving it, ZERO puts a digital seal (a signature) on it, made with a key that only exists in your browser. It works like the wax seal on an envelope: if anyone changes a single letter of the file —adds a company, deletes a line or changes a time—, the seal no longer fits.
- 4You check it here
This page checks the seal with your own browser's cryptography. Green: the file is exactly as ZERO wrote it. Red: someone changed it afterwards.
What is it for?
To show someone else what they tried to take from your browser —a lawyer, your country's data protection authority, a journalist, your employer—, with proof that you did not invent or edit it. Whoever gets it can check it themselves on this page, without installing anything.
What a receipt does not prove
That the list is complete (the receipt itself says what ZERO cannot see: other apps on the computer, isolated tabs, what each website's servers send on their own), nor what each company does with what it gets. It proves one thing, and proves it well: that the file was not changed.
Check your receipt
The sample is signed with a demonstration key, not anyone's.
The file is not sent anywhere: the check happens in your browser and makes no connection.
The key's fingerprint is like the serial number of the seal. Every browser has its own, shown in GUARDIANA ZERO › Settings. If the receipt's fingerprint matches a ZERO's, that receipt came from that browser.