PGP Fingerprint Verification: What MixTum's Signed Guarantee Actually Proves

Most Bitcoin mixing services offer some form of guarantee — a promise that they will process the order and deliver clean coins. But a promise and a cryptographic proof are fundamentally different things. MixTum issues a PGP-signed letter of guarantee for every order, and understanding what that signature actually proves is worth the explanation.

What Cryptographic Signing Means
A PGP (Pretty Good Privacy) signature works as follows: MixTum holds a private key. When an order is created, MixTum uses that private key to sign the guarantee letter. The resulting signature is mathematically tied to both the letter's content and MixTum's private key — two properties that matter enormously for trust.
First: the signature proves the letter was signed by the holder of that private key. If the public fingerprint matches — B8A5 CFCA F63F F2D8 384A 6B12 D3B2 8095 6F0E 7CAF — the letter came from MixTum, not from an impersonator.
Second: the signature proves the letter has not been altered since signing. Any modification to the letter's content — any single character changed — invalidates the signature. The letter is tamper-proof.
How to Verify
MixTum provides two verification paths. Users can verify the guarantee letter using Gpg4Win (a free PGP client for Windows) by checking the signature against MixTum's public key. Alternatively, the online PGP Checker at bitlist.co/pgp provides browser-based verification without requiring software installation.
What Verification Confirms
When verification succeeds, it confirms three things: the letter was signed by MixTum, the letter has not been modified since signing, and the terms within the letter — output address, amount, processing commitment — are the exact terms MixTum committed to at order creation.
For users concerned about accountability, this is a material distinction. A service that offers PGP-signed and verifiable guarantees is making a cryptographic commitment, not just a customer service promise. MixTum has maintained this standard since 2018, with USD 50,000 escrow on AltcoinsTalks.

Verify every guarantee with one fingerprint check → https://mixtum.io