Spec

Code snippets

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

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

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

Example response

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

{
    "data": {
        "notes": "Diameter and pitch in mm, stress in MPa, force in N, torque in N·m. Nut factor K ≈ 0.20 plain, 0.16 plated, 0.12 lubricated. Idealised — excludes joint stiffness and embedment relaxation.",
        "grades": {
            "8.8": {
                "yield_mpa": 640,
                "tensile_mpa": 800,
                "proof_stress_mpa": 580
            },
            "10.9": {
                "yield_mpa": 940,
                "tensile_mpa": 1040,
                "proof_stress_mpa": 830
            },
            "12.9": {
                "yield_mpa": 1100,
                "tensile_mpa": 1220,
                "proof_stress_mpa": 970
            }
        },
        "service": "bolttorque-api",
        "formulae": {
            "preload": "F = (percent/100)·σproof·As",
            "stress_area": "As = π/4·(d − 0.9382·P)²  (mm²)",
            "tensile_stress": "σ = F/As",
            "torque_tension": "T = K·D·F  (D in m, F in N, T in N·m)"
        },
        "endpoints": {
            "GET /v1/meta": "This document.",
            "GET /v1/torque": "Torque-tension T = K·D·F; solves tightening torque from preload or preload from torque.",
            "GET /v1/preload": "Target preload as a percentage of proof load, with tensile stress and tightening torque.",
            "GET /v1/stressarea": "Tensile stress area from nominal diameter and pitch, plus proof and yield loads."
        },
        "description": "Bolted-joint torque, preload and stress-area calculator for ISO metric fasteners. Torque-tension, tensile stress area from thread geometry, and preload from proof load."
    },
    "meta": {
        "timestamp": "2026-06-04T10:18:35.495Z",
        "request_id": "18b64249-ee4f-44fb-84a7-af95a3769e71"
    },
    "status": "ok",
    "message": "Meta",
    "success": true
}