HomeTwofish Encryption/Decryption

Twofish Encryption/Decryption

AES finalist algorithm, high-security symmetric encryption tool designed by Bruce Schneier

Key Features

Designed by Bruce Schneier's team
Supports 128, 192, 256-bit key lengths

Input Format / Output Format

About Twofish

Twofish is a symmetric key block cipher with a block size of 128 bits and key sizes up to 256 bits. It was one of the five finalists of the Advanced Encryption Standard (AES) contest, but was not selected for standardization. Twofish implies a high security margin and is flexible enough to be implemented in various environments.

AlgorithmTwofish
Key Size128, 192, 256 bits
Block Size128 bits (16 bytes)
StructureFeistel Network
Rounds16 Rounds

Key Features

Designed by Bruce Schneier's team
AES Competition Finalist (Rijndael won)
Supports 128, 192, 256-bit key lengths
128-bit block size (16 bytes), Feistel structure

Modes

CBC (Cipher Block Chaining): Most common mode, requires IV, highly secure. Recommended.
ECB (Electronic Codebook): Simplest mode, no IV. Insecure due to pattern leakage. Use with caution.
CFB (Cipher Feedback): Turns block cipher into stream cipher. Good for byte-oriented encryption.
OFB (Output Feedback): Turns block cipher into synchronous stream cipher. Errors do not propagate.

Common Use Cases

Supported by GPG (GNU Privacy Guard)
Encryption option in TrueCrypt / VeraCrypt
KeePass Password Safe database encryption
High-security environments requiring alternatives to AES

Security Note

There are no known effective cryptanalytic attacks on the full-round Twofish.
All calculations are performed locally in your browser using JavaScript.
Your keys and data are never sent to our servers.
Please keep your Key and IV safe. Losing them means losing your data.

Data is processed locally in your browser by default and will not be uploaded to any server. Upload will be clearly indicated if required.

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