What is Encrypt / Decrypt Studio?
JSON Web Encryption (JWE) wraps plaintext in a compact encrypted envelope for tokens and API payloads. Raw AES and asymmetric modes cover the same job without JOSE packaging — useful for debugging libraries, passphrases, and hybrid ECDH schemes.
This studio runs entirely in your browser via Web Crypto (and jose for JWE). Generate keys in memory, encrypt or decrypt, then Reset to clear sensitive fields.
How to use this tool
- Pick JWE, Symmetric (AES), or Asymmetric (RSA-OAEP / ECDH).
- Generate or paste a key (JWK / PEM / Hex / Base64) or use a passphrase for AES.
- Encrypt to a compact JWE or a JSON envelope { ciphertext, iv, tag?, salt? }, then decrypt on the other tab.
Frequently asked questions
Are encryption keys uploaded?
No. All modes run client-side with Web Crypto / jose and are not sent to stbox servers.
What does Authentication tag mismatch mean?
AES-GCM (and ECDH hybrid) failed integrity or key checks — wrong key/passphrase, IV, tag, or corrupted ciphertext.
Why prefer AES-GCM over AES-CBC?
GCM authenticates ciphertext. CBC with PKCS#7 padding encrypts but does not detect tampering unless you add a separate MAC.