How to sign a message using a bitcoin client
Posted by Matej (Support) on 05.12.2014 09:12:08
This is a way to prove you do possess a particular walet.
You can sign any message using your private key, creating an encrypted string - a signature. You then send the original message along with the signature (please make clear what is and what isn't a part of the message, and be aware that every character, including spaces, tabs and line breaks, is a part of the message).
We can then verify whether the signature was created using the private key you claim to own.
The message to be signed should express your request.
Before sending us your signed message please try if you are able to verify it. For example here: https://brainwallet.github.io/#verify
Start by choosing a wallet and copying its address to clipboard.
Then choose the menu option 'Tools | Sign Message'.
Enter the address and the message into the appropriate fields and press Sign Message.
Choose a wallet from Receive wallets and click Sign message
Enter the message into the appropriate field and press Sign message. The signature will appear in the Signature field.