ChaCha20-Poly1305 Stream Encryption Tool

Modern AEAD stream cipher, better mobile performance than AES-GCM, standard in TLS 1.3.

Settings

Key (Hex, 64 chars = 256 bits)

IV (Hex, 24 chars = 96 bits)

Additional Authenticated Data (AAD, optional)

Encrypt

Plaintext

Decrypt

Ciphertext (Hex)

Auth Tag (Hex)

Usage

!ChaCha20-Poly1305 is an AEAD (Authenticated Encryption with Associated Data) algorithm combining the ChaCha20 stream cipher with the Poly1305 message authentication code.

Fixed key length of 256 bits (32 bytes, Hex 64 chars)
Fixed IV length of 96 bits (12 bytes, Hex 24 chars), a different IV should be used for each encryption
AAD (Additional Authenticated Data) is not encrypted but is authenticated, used to protect protocol metadata
Authentication tag is used to verify ciphertext integrity, must be provided during decryption

Note: This tool is for learning and research only, not production-grade security. Based on @noble/ciphers pure JS implementation, works in all modern browsers.