Central Bank of Iceland Exchange Rate API: Official ISK Rates as JSON

The Central Bank of Iceland publishes the official exchange rates that accounting, tax, and customs rules in Iceland reference — published official rates, not moving market prices. This guide shows how to pull them as JSON: via a REST endpoint or the zero-dependency central-bank-of-iceland-exchange-rate npm package.

What the CBI publishes

• 10 official series against the króna — the major traded currencies plus the IMF SDR, a deliberately compact table.
• Registered once each business day, around 10:45 GMT.
• History back to 2016 — queryable by exact date or as a time series.
• The bank's own registration date on every response, so a rate is always citable.

The USD/ISK rate anchors the table alongside EUR/ISK — Iceland's tourism and export economy runs on both — and the once-daily registration is the official reference for Icelandic accounting and customs.

Why official rates, not market rates

A live mid-market feed answers "what is USD/ISK trading at right now?" — the right tool for checkouts and dashboards. But accountants, auditors, and tax authorities ask a different question: "which rate were you required to use for this date?" That answer comes from the Central Bank of Iceland's published rates, and it never changes after publication.

Get the latest rates (REST)

curl "https://allratestoday.com/api/v1/central-bank/cbi/latest" \
  -H "Authorization: Bearer YOUR_API_KEY"

The response is the bank's most recent published data — every rate and the publication date. The latest rates are available on every plan, including the free tier (300 requests/month, no credit card).

The npm SDK

npm install central-bank-of-iceland-exchange-rate

import { getRate, getLatestRates } from 'central-bank-of-iceland-exchange-rate';

// One pair at the official CBI rate
const pair = await getRate('USD', 'ISK', { apiKey: 'art_live_...' });
console.log(pair.rate, pair.rate_date);

// The bank's full published table
const table = await getLatestRates({ apiKey: 'art_live_...' });
console.log(table.rate_date, table.rates.length);

Zero dependencies, TypeScript types included, and it runs anywhere fetch exists — Node 18+, Bun, Deno, and edge runtimes.

Historical rates for an invoice date

import { getRatesForDate, getHistory } from 'central-bank-of-iceland-exchange-rate';

// The official rates for an invoice date — non-publication days return
// the most recent published date, flagged via published_on_requested_date.
const day = await getRatesForDate('2026-06-30', { apiKey: 'art_live_...' });

// Time series for one pair
const series = await getHistory(
  { source: 'USD', target: 'ISK', from: '2026-01-01' },
  { apiKey: 'art_live_...' }
);

Historical dates and time series need a paid plan; the latest rates stay free.

Published vs derived pairs

If the CBI does not print a pair directly, the API resolves it from the bank's published rates — an inverse, or a cross rate via ISK — and flags it derived: true with the method used. Official and computed values are never silently mixed, which is exactly the distinction an auditor will ask about.

A decade of króna history

The series runs from 2016, through the tourism-boom appreciation, the sharp pandemic reversal when visitors vanished, and the recovery since. A small table, but for one of the world's smallest free-floating currencies, the CBI's daily registration is the record everything official settles against.

FAQ

Does the Central Bank of Iceland have an official exchange rate API?

The CBI publishes its official rates on its own site, and AllRatesToday serves the same published rates as clean JSON via REST or the central-bank-of-iceland-exchange-rate npm package. The latest table is free.

How often do Central Bank of Iceland rates update?

Once each business day, registered around 10:45 GMT. These are published official rates, not moving market prices — every API response carries the registration date so you can cite it.

Can I get the CBI rate for a past date, like an invoice date?

Yes. The /central-bank/cbi/rates-for-date endpoint returns the official rates for any archived date. Non-publication days resolve to the most recent published date and are flagged, so your audit trail stays honest. Historical dates require a paid plan; latest rates are free.