National Bank of Cambodia Exchange Rate API: Official KHR Rates as JSON

The National Bank of Cambodia publishes the official exchange rates that accounting, tax, and customs rules in Cambodia 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 nbc-cambodia-exchange-rate npm package.

What the NBC publishes

• The official USD/KHR rate — the headline rate Cambodia's tax department requires for declarations.
• Bid, ask, and average rates for ~28 currencies against the riel.
• History back to 2016 — queryable by exact date or as a time series.
• The bank's own publication date on every response — NBC dates its table for the following day, and the API preserves that.

In a heavily dollarized economy the official USD/KHR rate is the number that matters: tax declarations, payroll conversion, and accounting all cite it.

Why official rates, not market rates

A live mid-market feed answers "what is USD/KHR 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 National Bank of Cambodia's published rates, and it never changes after publication.

Get the latest rates (REST)

curl "https://allratestoday.com/api/v1/central-bank/nbc/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 nbc-cambodia-exchange-rate

import { getRate, getLatestRates } from 'nbc-cambodia-exchange-rate';

// One pair at the official NBC rate
const pair = await getRate('USD', 'KHR', { 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 'nbc-cambodia-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: 'KHR', 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 NBC does not print a pair directly, the API resolves it from the bank's published rates — an inverse, or a cross rate via KHR — 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 riel history

The series runs from 2016, tracking the riel's managed band around 4,000 per dollar — narrow by design, which is exactly why auditors ask for the official print rather than a market feed.

FAQ

Does the National Bank of Cambodia have an official exchange rate API?

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

How often do National Bank of Cambodia rates update?

Once per business day, published in the afternoon and dated for the following day — the API preserves the NBC's own dating. Every response carries that publication date so you can cite it.

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

Yes. The /central-bank/nbc/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.