Encrypt & Decrypt Files with a Password (AES-256, in your browser)
Encrypt any file with a password entirely in your browser β the file never leaves your device. AES-GCM-256 with PBKDF2 (310,000 iterations); decrypt the .enc file the same way, offline.
π Runs entirely in your browser. Your input and output are never sent to a server or stored β fully private.
π Everything happens in your browser: the file and password never leave your device β nothing is uploaded or stored. Format: βTLE1β header + 16-byte salt + 12-byte IV + AES-GCM-256 ciphertext, key derived with PBKDF2-SHA-256 (310,000 iterations). If you lose the password the file cannot be recovered β there is no backdoor.
About this tool
Unlike upload-based encryption services, this tool never sees your data: the file and your password stay in the browser from start to finish. Pick any file, enter a password, and it is encrypted locally with AES-GCM-256, the key derived via PBKDF2-SHA-256 with 310,000 iterations. You get a portable .enc file you can store or share however you like; decrypting it later needs only this page and the same password. It works for documents, photos, archives β any file type β and keeps working offline once the page has loaded.
Frequently asked questions
What happens if I forget the password?
The file is unrecoverable β by design. The encryption key exists only as a function of your password, and no copy is kept anywhere: there is no server, no account and no reset link. That is exactly what makes the encryption trustworthy, because anyone able to recover your file without the password could also be an attacker. Store the password in a password manager before you delete the original file.
What if I type the wrong password when decrypting?
You get a clear error and nothing else β never a corrupted file. AES-GCM is authenticated encryption: it embeds an integrity tag that is checked before any data is returned, so a wrong password (or a tampered .enc file) fails cleanly. The 310,000 PBKDF2 iterations also make each password guess deliberately slow to compute, which turns brute-force attacks from millions of tries per second into a crawl.
Is my file uploaded anywhere during encryption?
No. The file is read into memory in your browser, encrypted there with the Web Crypto API, and saved back to your device β neither the file, the password nor the result is ever transmitted, logged or stored. Once the page has loaded you can even switch off your network connection and everything still works, which is an easy way to verify the claim yourself.