Collision probability

Code snippets

curl "https://api.oanor.com/birthdayparadox-api/v1/probability" \
  -H "x-oanor-key: oanor_test_..."

await fetch("https://api.oanor.com/birthdayparadox-api/v1/probability", {
  headers: { "x-oanor-key": "oanor_test_..." }
});

$ch = curl_init("https://api.oanor.com/birthdayparadox-api/v1/probability");
curl_setopt($ch, CURLOPT_HTTPHEADER, ["x-oanor-key: oanor_test_..."]);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
$out = curl_exec($ch);

import requests
requests.get(
    "https://api.oanor.com/birthdayparadox-api/v1/probability",
    headers={"x-oanor-key": "oanor_test_..."}
)

Example response

A real response from this endpoint, captured by the latest health check.

{
    "data": {
        "note": "Probability that at least two of n share a value among d equally likely options. With 23 people and 365 days it is about 50.7% — the famous birthday paradox.",
        "inputs": {
            "days": 365,
            "people": 23
        },
        "probability": 0.5072972343,
        "probability_percent": 50.729723,
        "no_match_probability": 0.4927027657
    },
    "meta": {
        "timestamp": "2026-06-05T19:50:10.985Z",
        "request_id": "f9705021-06e4-4558-bb05-4308a77f8014"
    },
    "status": "ok",
    "message": "Collision probability",
    "success": true
}