Runs in your browser · nothing uploaded

Encrypt Multiple Files into One Password-Protected Archive

Batch-encrypt many files with a single password into one downloadable .sealbox archive, and restore them all at once. AES-256-GCM per file, performed locally — no upload. SealBox Pro.

Loading tool…

More tools

All free, all private — everything runs in your browser.

Files

File Encryptor

Password-protect any file before you email or share it. AES-256-GCM with a PBKDF2-derived key, performed locally by your browser — no upload, no signup. Free.

Text

Text Encryptor

Turn any message into a shareable encrypted string and back. AES-256-GCM with PBKDF2 key derivation, performed locally by your browser. No upload, free.

TextPro

Encrypted Notes Vault

Keep private notes encrypted with a master password, stored only on your device. The master password derives an AES-256-GCM key and is never stored. 100% client-side. SealBox Pro.

Keys

AES Encryption Tool

Encrypt or decrypt with your own AES-128/256 key and IV in GCM or CBC mode. A raw, explicit bench for learning and development — runs entirely in your browser.

Keys

RSA Keypair Generator

Generate an RSA-OAEP keypair in your browser and export the public and private keys as PEM files. 2048, 3072, or 4096 bits. No upload, no server, free.

Keys

PBKDF2 Key Deriver

Derive a cryptographic key from a password with PBKDF2-HMAC-SHA256. Tunable iterations, random or custom salt, hex or base64 output. Runs in your browser.

How to use Bulk File Encryptor

  1. 1Pick the files you want to protect (any number — they are read locally, never uploaded).
  2. 2Enter one strong password, shared by every file in the archive. If lost, the files cannot be recovered.
  3. 3Click Encrypt — each file is sealed with its own fresh salt + IV (AES-256-GCM) and bundled into one .sealbox archive.
  4. 4Share the archive and the password through separate channels.
  5. 5To restore: open the .sealbox archive on the Decrypt tab, enter the same password, and every original file is downloaded.

Bulk File Encryptor FAQ

How does bulk encryption work?
Pick any number of files and enter one password. Each file is sealed individually with AES-256-GCM (a fresh random salt and IV per file, key derived with PBKDF2-SHA256) and bundled into a single .sealbox archive — a ZIP of per-file encrypted blobs plus a versioned manifest. Decrypt the archive with the same password to restore every original file. Nothing is uploaded.
Is bulk encryption a Pro feature?
Yes. Bulk encryption, the encrypted-notes vault, and custom encryption presets are SealBox Pro. The free single-file and single-text encryptors stay fully functional without a license — Pro adds the batch and vault conveniences on top.
What if I forget the password?
The files cannot be recovered — by design. There is no server, no reset link, and no copy of the key anywhere. AES-256-GCM is authenticated encryption, so a wrong password simply fails. Store the password safely before you share the archive.