Verify a CMDash proof receipt

A proof receipt is a small, signed JSON file that states one measurement. Drop or paste one below and this page checks it — the signature, the transparency log and the freshness window — entirely in your own browser. The receipt is never uploaded. You can try it with the illustrative sample below.

This page never asks CMDash whether a receipt is valid: if it did, “valid” would only mean “the server agrees with itself”. The only requests it makes for a receipt are the ones you ask for below, and they go only to the deployment you confirm.

Asking suppliers for proof? How relying parties request and read it.