Accurate conversions, no tables to maintain

Reference exchange rates updated every business day, history since 1999, and technical units from pascals to kilowatt-hours.

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GET

/v1/convert/currency

1 credit(s) per call

Converts an amount with the ECB reference rates (30 currencies, history since 1999).

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Result

—

Example request

curl "https://supercalcula.ch/api/v1/convert/currency?amount=100&from=CHF&to=EUR" \
  -H "Authorization: Bearer sk_live_…"

const res = await fetch("https://supercalcula.ch/api/v1/convert/currency?amount=100&from=CHF&to=EUR", {
  headers: { Authorization: "Bearer sk_live_…" },
});
console.log(await res.json());

import requests
r = requests.get("https://supercalcula.ch/api/v1/convert/currency",
    params={"amount":100,"from":"CHF","to":"EUR"},
    headers={"Authorization": "Bearer sk_live_…"})
print(r.json())

$ch = curl_init("https://supercalcula.ch/api/v1/convert/currency?amount=100&from=CHF&to=EUR");
curl_setopt_array($ch, [
  CURLOPT_HTTPHEADER => ["Authorization: Bearer sk_live_…"],
  CURLOPT_RETURNTRANSFER => true,
]);
$result = json_decode(curl_exec($ch), true);

Response

{
    "ok": true,
    "data": {
        "amount": 100,
        "from": "CHF",
        "to": "EUR",
        "rate": 1.0738,
        "result": 107.38,
        "date": "2026-10-09",
        "source": "ECB"
    }
}

Limits and cost

Cost : 1 credit(s) per call
Currencies: ECB rates, 30 currencies, history since 4 January 1999
Units: 12 categories, see GET /v1/units (free)
Precision: 0 to 12 decimals

Full reference in the documentation →

GET

/v1/convert/unit

1 credit(s) per call

Converts a value between units: length, mass, volume, area, temperature, speed, pressure, energy, power, data, time, angle.

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Result

—

Example request

curl "https://supercalcula.ch/api/v1/convert/unit?value=12.5&from=km&to=mi" \
  -H "Authorization: Bearer sk_live_…"

const res = await fetch("https://supercalcula.ch/api/v1/convert/unit?value=12.5&from=km&to=mi", {
  headers: { Authorization: "Bearer sk_live_…" },
});
console.log(await res.json());

import requests
r = requests.get("https://supercalcula.ch/api/v1/convert/unit",
    params={"value":12.5,"from":"km","to":"mi"},
    headers={"Authorization": "Bearer sk_live_…"})
print(r.json())

$ch = curl_init("https://supercalcula.ch/api/v1/convert/unit?value=12.5&from=km&to=mi");
curl_setopt_array($ch, [
  CURLOPT_HTTPHEADER => ["Authorization: Bearer sk_live_…"],
  CURLOPT_RETURNTRANSFER => true,
]);
$result = json_decode(curl_exec($ch), true);

Response

{
    "ok": true,
    "data": {
        "value": 12.5,
        "from": "km",
        "to": "mi",
        "result": 7.76714,
        "category": "length"
    }
}