192-bit · 64-bit optimized · Anderson/Biham 1995

Tiger hash generator

Tiger is a 192-bit (24-byte) cryptographic hash designed by Ross Anderson and Eli Biham for fast performance on 64-bit platforms. Uses 4 S-boxes (each 256×64-bit) and operates on 512-bit blocks with 24 rounds (3 passes × 8 rounds).

Tiger is a Merkle-Damgård hash with these characteristics: • Digest size: 192 bits (24 bytes, 48 hex characters) • Block size: 512 bits (64 bytes) • Rounds: 24 (3 passes of 8 rounds) • S-boxes: Four 256-entry × 64-bit lookup tables • Key schedule: XOR and addition of message words • `tiger()` runs 3 passes (regular, inverse, feed-forward) Tiger uses native 64-bit arithmetic with a nonlinear round function combining XOR, addition/subtraction, and S-box lookups. The 8-round inner loop mixes 3 state words (a, b, c) with message words X[0]–X[7]. Variants: • Tiger/192 — standard 192-bit output (3 passes) • Tiger/160 — truncated to 160 bits (2 passes) • Tiger/128 — truncated to 128 bits (2 passes) • Tiger2 — same algorithm, different padding byte (0x80 instead of 0x01) In-browser implementation is complex due to the 4 large S-box tables. For Tiger hashing, use: • openssl dgst -tiger (command-line) • tiger crate (Rust) • tiger or tigerhash (npm)

How to use this tool

  1. Read the Tiger hash characteristics panel for the algorithm's fixed parameters: digest size, block size, rounds, and S-box layout.
  2. Study the round summary — Tiger runs 3 passes (regular, inverse, feed-forward) of 8 rounds each, mixing three 64-bit state words a, b, c with message words X[0]–X[7].
  3. Check the Variants list to understand the difference between Tiger/192, Tiger/160, Tiger/128, and Tiger2.
  4. To actually compute a Tiger digest, use one of the referenced tools — for example openssl dgst -tiger on the command line, the tiger crate in Rust, or the tiger npm package.
  5. Note that this page is a reference only: it does not hash input in your browser, so there are no inputs, buttons, or copy actions to operate.

Why this tool is helpful

Understand Tiger's design

See exactly how a 192-bit Merkle–Damgård hash is built — 512-bit blocks, 24 rounds, and four 256-entry S-boxes — all summarized in one panel.

Learn why it's 64-bit optimized

Tiger was designed for fast performance on 64-bit RISC architectures. The reference explains how its round function uses native 64-bit arithmetic, S-box lookups, and additions to beat SHA-1 and MD5.

Distinguish the variants

Quickly tell Tiger/192 apart from the truncated Tiger/160 and Tiger/128, and understand why Tiger2 (with its 0x80 padding byte) is the recommended variant today.

Recognize real-world usage

Tiger is used in the Direct Connect P2P protocol and TigerTree hashing. This page gives the background you need before integrating it.

Pick the right implementation

Find ready-made options — openssl dgst -tiger, the Rust tiger crate, or the tiger / tigerhash npm packages — for when you need a working digest.

Read it offline, privately

The page is static and reference-only. It loads no external scripts and never collects, stores, or transmits any input.

FAQ

What is the Tiger hash?

Tiger is a 192-bit cryptographic hash function designed by Ross Anderson and Eli Biham in 1995, optimized for fast performance on 64-bit platforms. It produces a 24-byte (48 hex character) digest.

Does this page compute Tiger hashes?

No. This is an education and reference page only — there is no input box and no hashing runs in your browser. To compute a digest, use one of the referenced tools such as openssl dgst -tiger.

How does the Tiger algorithm work?

Tiger is a Merkle–Damgård hash that processes 512-bit blocks through 24 rounds (3 passes of 8). Each round mixes three 64-bit state words a, b, c with message words X[0]–X[7] using XOR, addition/subtraction, and four 256-entry S-box lookups.

What are Tiger/160 and Tiger/128?

They are truncated variants. Tiger/192 is the full output, while Tiger/160 and Tiger/128 shorten the digest to 160 and 128 bits respectively by reducing the number of passes to 2.

What is Tiger2 and how is it different?

Tiger2 is the same algorithm with a different padding byte — 0x80 instead of 0x01. It fixes a minor padding issue in the original Tiger and is the currently recommended variant.

How is a Tiger digest represented?

A Tiger/192 digest is 192 bits, shown as 24 bytes or 48 hexadecimal characters. Like other hashes, it is a fixed-length fingerprint of arbitrary input and is case-insensitive in hex form.

Does any data leave my browser?

No. The page is fully static and contains no scripts that read or send your input. Nothing is uploaded, logged, or transmitted to any server.