MurmurHash Generator
Compute MurmurHash3 hashes in 32-bit or 128-bit from any text.
How to use the MurmurHash Generator
- Type or paste your text in the box.
- Pick the variant — 32-bit suits most hash-table work.
- The hash appears as you type; click Copy to grab it.
About the MurmurHash Generator
MurmurHash3 was created by Austin Appleby and became the default answer to “what should I hash my keys with?” for a whole generation of infrastructure code. The name comes from its inner loop — multiply, rotate, multiply, rotate — a handful of cheap CPU instructions repeated over blocks of the input, followed by a finalisation step that avalanches the bits. It is not a checksum and not a cryptographic hash: it is a distribution hash, built to turn keys into numbers that scatter evenly across buckets, which is why it is so common in hash tables and Bloom filters.
The variant names need explaining, because two of them look interchangeable and are not. murmur3a is the 32-bit version and gives 8 hexadecimal characters. murmur3c and murmur3f are both 128-bit and both give 32 hexadecimal characters, but they are separate algorithms — one tuned for 32-bit x86 CPUs, one for 64-bit x64 — and they produce completely different output for the same input. They are not two implementations of one hash; picking the “wrong” one will not match the other system you are trying to talk to. If you are comparing hashes with another tool or library, you must match the exact variant it used.
Choose 32-bit unless you have a reason not to: it is the fastest and 8 characters is plenty for ordinary bucketing. Step up to a 128-bit variant when you are hashing very large key sets and want accidental collisions to become vanishingly unlikely, or when you need a compact identifier for deduplication. None of them are safe against an attacker — MurmurHash3 collisions can be produced deliberately, and hash-flooding attacks against services that used it unprotected are a real, documented problem. For anything adversarial, reach for SHA-256; even MD5 is in a different category of difficulty.
Frequently asked questions
What is the difference between murmur3c and murmur3f?
Both are 128-bit and both output 32 hex characters, but they are different algorithms — murmur3c is tuned for x86 and murmur3f for x64. The same input gives different results, so you must pick the exact variant the other system uses.
Which variant should I choose?
MurmurHash3 32-bit for normal hash-table and bucketing work. Use a 128-bit variant when you have huge key sets or want a compact ID where accidental collisions must be extremely rare.
Is MurmurHash secure?
No. It is a fast distribution hash with no attack resistance — collisions can be crafted on purpose, which has been used for hash-flooding denial-of-service attacks. Never use it for passwords, signatures or tamper detection.
What is MurmurHash good for?
Hash tables, Bloom filters, sharding, partitioning and cache keys — anywhere you need keys spread evenly and quickly and nobody is trying to game the result.
Is my text sent anywhere?
Your text is sent to our server to be hashed, because browsers cannot compute MurmurHash. It is hashed and immediately discarded — never logged, never stored.