Encrypted Note
AES-256 encrypt a note with a passphrase, and decrypt it back.
About Encrypted Note
Encrypted Note encrypts text with AES-256-GCM, deriving the key from your passphrase using PBKDF2 at 250,000 iterations. The output is a base64 blob you can paste anywhere — an email, a note app, a document — that is unreadable without the passphrase. A random salt and nonce are generated each time, so encrypting the same text twice produces different output.
How to use it
- Paste your text and choose a strong passphrase.
- Click Encrypt and copy the blob.
- To read it back, switch to Decrypt, paste the blob and enter the same passphrase.
Questions
How strong is this?
AES-256-GCM is the standard used for government-classified material, and it runs through the browser’s own Web Crypto API rather than a hand-rolled implementation. The weak link is your passphrase, not the cipher.
What if I forget the passphrase?
The note is permanently unreadable. There is no recovery, no reset and no backdoor — that is what makes the encryption meaningful.
Why does the same text produce different output each time?
A fresh random salt and nonce are used per encryption. That is deliberate: identical output would reveal that two messages are the same.
Is this safe for sharing secrets with someone?
The encryption is sound, but you still have to get the passphrase to them through a separate channel. Never send the passphrase alongside the blob.
Encrypted Note is free and runs entirely in your browser. No account, no upload, no watermark, no limit on use.