There are a few reasons you may need to be able to prove who you are without revealing who you are.

Suppose you desire to share many different pieces of information online but must remain anonymous for security reasons. Since you are anonymous, you have no reputation online and therefore no trust or credibility.
You can release one piece of information that will later prove to be true, thus gaining credibility for yourself. People will now take your information seriously, except you were fully anonymous, so that credibility is useless to you as you can't claim it in the future when sharing future information.
What's worse, others may impersonate you, claiming to be the original author of the first piece of information, and then share bad information thus soiling all of the credibility you built up.

With AnoProof you can sign your first piece of information with an AnoProof signature using your AnoProof secret key.
Now, once it gains credibility, you can sign your future informations with your same secret key.
Using AnoProof, anyone can verify that the future information (signed) was authored by the same anonymous author as the original credible information.

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AnoProof doesn't always have to be used anonymously, another great use-case for AnoProof is in proving your known identity, online, in an ever increasing world of spoofing, deep-fakes, and general impersonation.

Consider the case of Leoni AG, in which the CEO instructed the CFO to wire transfer $40m to an offshore account, the only problem for the CFO, it wasn't a true eMail from the CEO, it was a hacker pretending to be the CEO.
Had the company policy been that all instructions of such nature must be signed with an AnoProof signature, the CFO could have easily proven that the hackers weren't the CEO.

This example was just a simple eMail spoofing, but imagine a few years from now when DeepFakes, SIM spoofing, and a combination of other tools will allow a hacker to video call one of your employees, and pretend to be you not only with caller ID but visibly and audibly as well.
Signing protocols like AnoProof will become more and more necessary in the identity verification crisis realm AI will bring us towards.

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To use AnoProof, simply paste, verbatim, two messages that have AnoProof signatures, in the text boxes at the bottom of this page, then tap the 'Verify' button.

If you wish to sign your own AnoProof messages, please go here.

To use AnoProof, simply paste, verbatim, two messages that have AnoProof signatures, in the text boxes at the bottom of this page, then tap the 'Verify' button.

If you wish to sign your own AnoProof messages, please go here.

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Technical Explanation of the Protocol follows:

The AnoProof protocol takes a message as an input, this message is M.
The message is hashed using SHA256, then asymmetrically encrypted with a secret key. This encrypted hash is S.
The public key associated with the secret key is P.
The signed message then takes the form {M + '\n\nAnoProof:' + S + P}

With this, one can prove that the message was authored by the holder of the secret key, by:
1) Extracting M from a signed message and hashing it to get A1
2) Extracting S and decrypting it with P to get A2.

If A1 and A2 are identical, then the message was signed by the holder of the secret key.
If two messages are both shown to be signed by the holder of their secret key AND their P values are the same, then they are definitively signed by the holder of the same secret key.

• AnoProof encodes S and P into a custom base256 encoding which starts at the 256th unicode character and increments from there. This scheme was designed so that the characters are guaranteed printable and the entire AnoProof signature can fit within less than 1/2 of the size of a tweet.

• AnoProof uses Elliptic Curve cryptography from the NaCl Library, utilizing Curve ed25519, which is why the logo of AnoProof incorporates two connected Twisted Edwards Curves.