Spec

Code snippets

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

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

$ch = curl_init("https://api.oanor.com/relativity-api/v1/meta");
curl_setopt($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/relativity-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": "c = 299,792,458 m/s. Velocity via 'velocity' (m/s), 'velocity_kms', or 'beta' (v/c); β must be < 1. Energies reported in J, eV and kWh.",
        "service": "relativity-api",
        "formulae": {
            "energy": "E = γmc², KE = (γ−1)mc², p = γmv",
            "lorentz": "γ = 1/√(1 − β²), β = v/c",
            "mass_energy": "E = mc²",
            "time_dilation": "Δt = γ·Δt₀",
            "length_contraction": "L = L₀/γ"
        },
        "endpoints": {
            "GET /v1/meta": "This document.",
            "GET /v1/energy": "Rest, total and kinetic energy and relativistic momentum from mass and velocity.",
            "GET /v1/lorentz": "Lorentz factor from a velocity, with optional time dilation and length contraction.",
            "GET /v1/mass-energy": "Convert between mass and energy via E = mc²."
        },
        "description": "Special-relativity calculator: Lorentz factor with time dilation and length contraction, relativistic energy and momentum, and mass–energy equivalence (E = mc²)."
    },
    "meta": {
        "timestamp": "2026-06-04T18:38:05.561Z",
        "request_id": "07c7910f-9ae7-4ad9-a6cc-27924805dfce"
    },
    "status": "ok",
    "message": "Meta",
    "success": true
}