Free online Rabbit stream cipher tool for fast text encryption and decryption. Supports 128-bit keys and 64-bit IVs to quickly secure sensitive data.
Enter input and key, then encrypt or decrypt

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When you need to quickly encrypt text data in transit but worry about the inefficiency of traditional algorithms, the Rabbit stream cipher tool offers a lightweight solution. Based on the Rabbit synchronous stream cipher algorithm, this tool generates a keystream using a 128-bit key and a 64-bit initialization vector (IV). It encrypts data by performing an XOR operation between each byte of the original text and the keystream, while the reverse operation decrypts it. The encrypted result is output as a hexadecimal string, and decryption restores the original plaintext.
Q: What are the key format requirements?
You must use a 16-byte hexadecimal string (32 characters), such as 00112233445566778899aabbccddeeff.
Q: What scenarios is the Rabbit algorithm suitable for?
Due to its high throughput, it is particularly suitable for real-time communication encryption (such as IoT device data transmission), log protection, and other scenarios requiring fast processing of continuous data streams. However, it is not recommended for high-security storage scenarios.
Encryption and decryption must use the exact same key and IV. The maximum text processing length is limited by your browser's memory. Do not use this tool for highly sensitive data such as military or financial information. If the key is lost, the data cannot be recovered.
In a testing environment, you can try this typical parameter combination: using the key "00000000000000000000000000000000" with the IV "0000000000000000" to encrypt "Hello" will output "a3f5e6". Please note that the Rabbit algorithm was not included as a recommended algorithm in the final evaluation of the eSTREAM project due to specific attack vectors. For actual production environments, it is recommended to use NIST-certified algorithms such as AES-GCM.