Trust the math, not the server.
PublishingPolicy.org uses cryptography to give publishers the receipts—providing undeniable proof of their integrity and shielding them from bad-faith accusations.
What is a Cryptographic Seal?
Every time a publisher updates their policy, our system takes the exact text of that policy and runs it through a standard mathematical algorithm called SHA-256. This generates a unique string of characters—a mathematical fingerprint of the document.
Undeniable Proof
If a publisher were to secretly change even a single comma in their policy, the SHA-256 math would output a completely different fingerprint. This means when an audience questions their standards, the publisher has the mathematical receipts to prove their word is their bond.
Independent Verification
A standard URL relies on trusting a central server. A cryptographic seal means readers don't have to take our word for it—or the publisher's. Anyone can run the SHA-256 math on their own computer, turning a simple policy into an ironclad trust signal.
How to Verify a Seal Yourself
You don't need any special software to verify a policy's authenticity. You can use standard tools built into your computer to independently verify the math.
- 1. Download the Cryptographic Receipt
From the policy's timeline, download the Canonical Receipt (
.json). This file contains the exact, byte-for-byte structured data that was hashed—including the policy text and the publisher's identity. This prevents copy-paste formatting errors. - 2. Run the SHA-256 algorithm
Open your computer's terminal (no special software required).
On Mac/Linux:shasum -a 256 receipt.json
On Windows:CertUtil -hashfile receipt.json SHA256 - 3. Compare the output to the public ledger
Look at the resulting string of characters. It should perfectly match the seal number recorded on the policy's public timeline for that date. If it matches, the document is 100% authentic and unaltered.