Xoroshiro256** is a large-state, high-quality pseudo-random number generator with a 256-bit state space. Adopted as the default PRNG for .NET 6+, GNU Fortran, and Lua, it features a multiplication-based scrambler (multiply by 5, rotate, multiply by 9) providing excellent statistical properties. With a period of 2^256-1, it’s ideal for parallel and distributed computing via jump functions.
| Property | Value |
|---|---|
| Category | Random Number Generators |
| Sub-category | Non-Cryptographic PRNG |
| Security status | 🎓 Educational Only |
| Complexity | Intermediate |
| Inventor | David Blackman, Sebastiano Vigna |
| Year | 2018 |
| Origin | 🇮🇹 Italy |
| Source | algorithms/random/xoroshiro256starstar.js |
| Parameter | Supported values |
|---|---|
| Seed sizes | 8 bytes (64 bits) |
| Flag | Value |
|---|---|
IsDeterministic |
Yes |
IsCryptographicallySecure |
No |
Status: 🎓 Educational Only
No vulnerabilities are recorded for this implementation.
4 vectors ship with this algorithm and run in the test suite. Byte values are hexadecimal.
Vector 1 — Seed=0: First four 64-bit outputs from xoroshiro256**
| Field | Value |
|---|---|
seed |
0000000000000000 |
outputSize |
32 |
input |
null |
expected |
a9c29cbd46a8701a809e2bcd50f20e6a27ffc289755a32610ab72b6a53f8cc21 |
Vector 2 — Seed=1: First four 64-bit outputs from xoroshiro256**
| Field | Value |
|---|---|
seed |
0100000000000000 |
outputSize |
32 |
input |
null |
expected |
c326090b373e88c51cf8710fb8741b02cec8e54967f08d26f2fe7a667d7552e0 |
Vector 3 — Seed=12345: First four 64-bit outputs
| Field | Value |
|---|---|
seed |
3930000000000000 |
outputSize |
32 |
input |
null |
expected |
da09229a72dbf22c9fc82a900bf85cd626166d0d4186ec8afb3906563dec5562 |
Vector 4 — Seed=0xDEADBEEF: First four 64-bit outputs
| Field | Value |
|---|---|
seed |
efbeadde00000000 |
outputSize |
32 |
input |
null |
expected |
b5b035fcf4c269becd3000f6ac4a47b201c78db74b901c6f8494e508fcfd84ea |