Taiwan Central Bank Exchange Rate API: Official NTD/USD Closing Rates as JSON

The Central Bank of the Republic of China (Taiwan) publishes the official exchange rates that accounting, tax, and customs practice in Taiwan 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 taiwan-central-bank-exchange-rate npm package.

One series, and why it is the right one

Taiwan’s central bank publishes exactly one exchange-rate series of its own: the NTD/USD interbank spot closing rate, sourced from Taipei Forex Inc. The multi-currency boards you see in Taiwan are commercial bank rates — not central bank publications. If a filing or audit needs “the official Taiwan rate”, this closing rate is it; other pairs resolve as crosses and are flagged as derived.

Why official rates, not market rates

A live mid-market feed answers "what is USD/TWD 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 the Republic of China (Taiwan)’s published rates, and it never changes after publication.

Get the latest rates (REST)

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

The response is the bank's most recent published table — 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 taiwan-central-bank-exchange-rate

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

// One pair at the official rate
const pair = await getRate('USD', 'TWD', { 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 'taiwan-central-bank-exchange-rate';

const day = await getRatesForDate('2026-08-18', { apiKey: 'art_live_...' });

const series = await getHistory(
  { source: 'USD', target: 'TWD', 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 Central Bank of the Republic of China (Taiwan) does not print a pair directly, the API resolves it from the bank's published rates — an inverse, or a cross via TWD — 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.

The archive

The bank’s open data carries every business-day close back to January 2008 — through the 2008 crisis, the 2020 COVID spike above 30.5, and the recent strength below 32.

FAQ

Does the Central Bank of the Republic of China (Taiwan) have an official exchange rate API?

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

How do I get the official Taiwan exchange rate for a past date?

The rates-for-date endpoint returns the official table for any archived date; non-publication days resolve to the most recent published date and are flagged, so audit trails stay honest. Historical dates require a paid plan; latest rates are free.

Does Taiwan’s central bank publish rates for currencies other than the US dollar?

No — the NTD/USD interbank closing rate is its only own series. Other pairs are computed from published rates as crosses and always flagged derived: true.