Good enough security for ordinary people — encrypt files and messages, sign your work, all inside your browser. No installation, no account, no data ever leaves your device.
SBOsecure uses public-key cryptography. You have two keys:
- Public key — share this freely. Anyone with it can send you encrypted files.
- Private key (inside your keyset file) — keep this secret. Only you can decrypt what was sent to you.
Everything runs locally. The page has no server-side component and makes no network requests with your data.
- Open the My Keys tab and click Create new key.
- Enter a name, a password, and choose an iterations value (higher = more secure).
- Click Create new key set and immediately download the keyset file — it will not be recoverable if you close the page without saving.
- Download your public key (
public.jwks.json) and share it with anyone who needs to send you encrypted files.
- Go to My Keys → Load key.
- Select your saved keyset file, enter your password and iterations number, then click Load key.
- Go to the Contacts tab and add the recipient — load their
public.jwks.jsonfile. - Open the Encrypt tab, type your message or select a file.
- Check the recipient(s) you want to send to.
- Click Encrypt and download the resulting
.sbo.jsonfile. Send it to the recipient by any means (email, messenger, file transfer).
If your own keys are loaded, the package is automatically signed so the recipient can verify it came from you.
- Make sure your keys are loaded (My Keys tab).
- Go to the Decrypt tab and either paste the
.sbo.jsoncontent or load the file. - Click Decrypt. If the package was signed, SBOsecure will show whether the signature is valid.
No keys required. Go to Password Enc. to encrypt or decrypt text with just a password. You must remember the exact password and the iterations number — both are needed to decrypt.
| Keys are session-only | Closing or refreshing the page clears loaded keys. Always save your keyset file. |
| Keyset file is sensitive | It contains your private key encrypted with your password. Treat it like a password manager file. |
| Contacts are session-only | Use Download all in the Contacts tab to save your contacts between sessions. |
| HTTPS required | Browser security requires the app to be served over HTTPS. It will not work over plain HTTP. |
SBOsecure uses standard algorithms provided by your browser's built-in Web Crypto API: AES-256-GCM for content encryption · RSA-OAEP-2048 for key wrapping · RSASSA-PKCS1-v1_5 for signatures · PBKDF2-SHA-256 for password-derived keys.
SBOsecure is free software licensed under the GNU General Public License v3. Source: github.com/SBOsoft/SBOsecure