# Cyan4973/xxHash

Extremely fast non-cryptographic hash algorithm

Repository: https://github.com/Cyan4973/xxHash
Canonical: https://ross.abutalabs.com/products/xxhash
Homepage: http://www.xxhash.com/
Language: C
License: NOASSERTION
License Family: other
Topics: xxhash, smhasher, hash-functions, c, dispersion, hash, hash-checksum
Last push: 2026-07-27T13:42:29+00:00

## Health v2 (maintenance only)
Score: 65/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 94, release rhythm 8, longevity 100
- inputs: {"age_days": 4508, "days_push": 37, "days_rel": 611, "gap_med": null, "n_releases_24m": 1}
- flags: no_license
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 11220, forks 912 (observed 2026-08-28T04:10:46.473755+00:00)

## What it is
xxHash is an extremely fast non-cryptographic hash algorithm library written in C, offering XXH32, XXH64, and the modern XXH3 family (64- and 128-bit variants). It runs at RAM speed limits, is highly portable across platforms and endiannesses, and passes the SMHasher quality test suite.

## Use cases
- fast checksums for files or data blocks
- hash table key hashing in performance-critical code
- data deduplication fingerprints
- detecting data corruption in storage pipelines
- consistent hashing across platforms and endiannesses
- benchmarking hash function throughput

## When to choose
- you need maximum hashing speed at RAM bandwidth limits
- you need identical hash values across platforms and endiannesses
- you need high-quality non-cryptographic hashes validated by SMHasher
- you need 32-, 64-, or 128-bit hash widths including SIMD-accelerated XXH3

## When to avoid
- you need cryptographic security against adversarial inputs (use SHA-256/Blake3)
- you need keyed hashes resistant to hash-flooding (use SipHash)
- your environment lacks a C compiler and you need a pure high-level-language implementation

## Facets
- artifact type: library
- maturity: stable
- function: cryptography, serialization, developer-tools
- domain: performance, developer-tools, databases
- platform: cross-platform, cpp, c
- tags: hash-function, non-cryptographic, checksum, xxhash, smhasher, simd, algorithms

## Member repositories
- Cyan4973/xxHash (main) score 65

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:10:46.473755+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-29T17:16:26.349877+00:00, confidence not recorded.
  - readme: https://github.com/Cyan4973/xxHash (fetched 2026-08-28T04:10:46.473755+00:00, sha 133f9632bb61)
  - homepage: http://www.xxhash.com/ (fetched 2026-08-29T08:14:58.420265+00:00, sha d1623a906abc)
  - site_page: https://xxhash.com/doc/v0.8.3/index.html (fetched 2026-08-29T08:14:58.430017+00:00, sha e4160cf52be2)
- Data as of 2026-08-30T08:39:29.467469+00:00.