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Data provider: —
Randomness from the sky
Random numbers,
seeded by the atmosphere.
Live weather observations from airports around the world feed an entropy pool. Every result also mixes in fresh randomness from the server's operating system, so it stays unpredictable even though weather reports are public.
1 — 100— stations
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Entropy snapshot—
01 / Generate
Pick a generator.
Results are unbiased: every value in the range has exactly the same chance.
Results
Your numbers will appear here.
02 / Entropy source
Where the randomness comes from.
Every ten minutes the server downloads the latest METAR weather reports and stirs them into its entropy pool. Here is the data behind the numbers you are drawing now.
How it works
- Observe. Temperature, dew point, pressure, and wind from 48 airports on six continents.
- Mix. The full report is hashed with SHA-256 into a pool that already holds operating system randomness.
- Draw. Each request derives a fresh HMAC-SHA256 stream and uses rejection sampling, so no value is favored.
Latest observations
—| Station | Location | Observed (UTC) | Temperature | Pressure | Wind |
|---|---|---|---|---|---|
| Loading atmospheric data… | |||||
Weather observations are public, so on their own they are not secret. That is why the pool always combines them with the server's cryptographic random number generator. Use this site for games, draws, sampling, and experiments; generate passwords and encryption keys on your own device.
03 / API
Use the random API.
Free JSON endpoints with up to 1,000 values per request and 60 requests per minute for each visitor.
curl "https://random.math7.com/api/random/integers?min=1&max=6&count=5"
{"integers":[4,1,6,6,2],"min":1,"max":6,"count":5,"unique":false,...}
curl "https://random.math7.com/api/random/integers?min=1&max=49&count=6&unique=true"
curl "https://random.math7.com/api/random/decimals?count=3&places=8"
curl "https://random.math7.com/api/random/source"