Signed Note

Sign a text message with your digital signature. Like signing a letter, but cryptographically secure.

What is this?

Think of this like signing a paper document, but digital. When you sign a message:

  • • Anyone can verify it really came from you
  • • No one can fake your signature
  • • Any changes to the message will break the signature

Try it below - type a message, hit sign, and see how it works. You can also enable encryption to make the message readable only by the intended recipient.

Sign Your Message

Write anything you want to sign. Could be a note, a promise, or just "hello world".

How Digital Signatures Work

The Process

  1. 1. You have a key pair: A private key (secret) and public key (shareable)
  2. 2. Signing: Your private key creates a unique signature for your message
  3. 3. Verifying: Anyone with your public key can prove you signed it
  4. 4. Tampering: Change even one letter and the signature breaks

Why This Matters

  • • Software updates (proving they are from the real company)
  • • Legal documents (digital contracts)
  • • Cryptocurrency (proving you own your coins)
  • • Email security (proving emails are not spoofed)

The Format

Your signed message looks like this:

~~~
Your message goes here
~~~
your-public-key-here
signature-goes-here

Simple, readable, and cryptographically secure.