Tyre change: speedo error

Code snippets

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

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

$ch = curl_init("https://api.oanor.com/tirecalc-api/v1/compare");
curl_setopt($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/tirecalc-api/v1/compare",
    headers={"x-oanor-key": "oanor_test_..."}
)

Example response

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

{
    "data": {
        "new": "225/45R17",
        "note": "the new tyre is larger — the speedometer under-reads (you go faster than shown)",
        "original": "205/55R16",
        "actual_speed": 100.38,
        "new_diameter_mm": 634.3,
        "speedometer_reads": 100,
        "original_diameter_mm": 631.9,
        "diameter_difference_mm": 2.4,
        "diameter_difference_percent": 0.3798
    },
    "meta": {
        "timestamp": "2026-06-03T17:42:02.795Z",
        "request_id": "9895e249-6638-471a-ac6b-a6e7eb62748a"
    },
    "status": "ok",
    "message": "Tire comparison",
    "success": true
}