U.S. Department of the Treasury Exchange Rates API — ustreasury-exchange-rate

Official U.S. Department of the Treasury (the United States) quarterly exchange rates for Node.js and TypeScript. The published tax authority rates behind tax filings, customs valuations, audits, and compliant invoicing — not market estimates, but the numbers U.S. Department of the Treasury itself prints, every quarter.

🚀 Why this client?

• 🏛️ Official published rates — U.S. Department of the Treasury's own table, with the publisher's own rate_date on every response
• 📅 History back to 2001 — point-in-time tables and daily series for any past date
• 🔀 Published vs derived, always flagged — computed inverse/cross pairs carry derived: true, never mixed with official prints
• ⚡ Zero dependencies — pure ESM + CJS over global fetch; Node 18+, Bun, Deno, and edge runtimes
• 🔷 Type-safe — full TypeScript definitions shipped with the package
• 🧾 Compliance-grade metadata — rate_type, publication date, and source disclaimer on every response

Official rate, not mid-market: every value here is a number U.S. Department of the Treasury itself published, fixed once printed and carrying the tax authority's own rate_date — what filings and audits require. Need the live mid-market rate for pricing or display instead? Use the mid-market API or @allratestoday/sdk. The two can diverge by several percent.

🔑 Get your API key

Get a free API key at allratestoday.com/register — no credit card required. Latest rates are on every plan, including free.

📈 Latest published table

The image is rendered live from the keyless endpoint, so it follows the tax authority's publications on npm and on GitHub alike without a new release. The same table as text is folded below for search and copy-paste: on GitHub a daily Action refreshes it whenever the tax authority publishes a new table; on npm it is as of the package's publish date.

Base	Quote	Type	Rate
USD	AED	quarterly	3.673
USD	AFN	quarterly	65.15
USD	ALL	quarterly	80.75
USD	AMD	quarterly	360
USD	AOA	quarterly	913
USD	ARS	quarterly	1545
USD	AUD	quarterly	1.435
USD	AZN	quarterly	1.7
USD	BAM	quarterly	1.722
USD	BBD	quarterly	2.02
USD	BDT	quarterly	124
USD	BGN	quarterly	0.87
USD	BHD	quarterly	0.377
USD	BIF	quarterly	3443
USD	BMD	quarterly	1
USD	BND	quarterly	1.277
USD	BOB	quarterly	11.96
USD	BRL	quarterly	5.205
USD	BSD	quarterly	1
USD	BWP	quarterly	13.889
USD	BYN	quarterly	3.029
USD	BZD	quarterly	2
USD	CAD

Full table on the U.S. Department of the Treasury rates page · Source: Official rates published by USTREASURY, served by AllRatesToday. Rates are as printed by the tax authority; AllRatesToday is not affiliated with it.

📦 Installation

npm install ustreasury-exchange-rate

yarn add ustreasury-exchange-rate

pnpm add ustreasury-exchange-rate

Requires Node 18+ (global fetch); also runs on Bun, Deno and edge runtimes. Also published under the org scope as @allratestoday/ustreasury-exchange-rate — same code, same versions.

🏁 Quick start

import { getRate } from 'ustreasury-exchange-rate';

const pair = await getRate('USD', 'EUR', { apiKey: 'art_live_...' });
console.log(pair.rate, pair.rate_date); // the official U.S. Department of the Treasury rate, on the tax authority's own date

📚 API reference

• Latest pair rate — one pair from the latest published table
• Full published table — everything the tax authority printed, in one call
• Table for a date — the official table for an invoice or filing date
• Daily time series — one pair across a date range

---

Latest pair rate

Free plan and up. Pairs the tax authority does not print directly are resolved from its table and flagged (see Published vs derived rates below).

const pair = await getRate('USD', 'EUR', { apiKey: 'art_live_...' });

Response:

{
  bank: 'ustreasury',
  name: 'U.S. Department of the Treasury',
  rate_date: '2026-09-30',   // U.S. Department of the Treasury's own publication date
  source: 'USD',
  target: 'EUR',
  rate: 0.881,
  rate_type: 'quarterly',
  derived: false,
  method: 'published',
  disclaimer: 'Official rates as published by the named central bank. On weekends/holidays the most recent published rate_date is returned.'
}

Full published table

Free plan and up. The complete table for the latest publication date.

import { getLatestRates } from 'ustreasury-exchange-rate';

const table = await getLatestRates({ apiKey: 'art_live_...' });
console.log(table.rate_date, table.rates.length);

Response:

{
  bank: 'ustreasury',
  name: 'U.S. Department of the Treasury',
  rate_date: '2026-09-30',
  rates: [
    { "base": "USD", "quote": "EUR", "type": "quarterly", "value": 0.881 },
    // … the rest of the published table (145 currencies vs USD)
  ],
  disclaimer: '…'
}

Table for a date

Paid plans. The official table for any date since 2001 — weekends and holidays return the most recent published date, flagged via published_on_requested_date, which is exactly the in-force rate a filing needs.

import { getRatesForDate } from 'ustreasury-exchange-rate';

const day = await getRatesForDate('2026-06-30', { apiKey: 'art_live_...' });
// Optionally narrow to one pair:
const one = await getRatesForDate('2026-06-30', { apiKey: 'art_live_...', source: 'USD', target: 'EUR' });

Response:

{
  bank: 'ustreasury',
  requested_date: '2026-06-30',
  rate_date: '2026-06-30',                // the date actually published
  published_on_requested_date: true,      // false when a weekend/holiday fell back
  rates: [ /* the full table for that date */ ],
  disclaimer: '…'
}

Daily time series

Paid plans. One resolved rate per publication date — ready for charting, revaluation runs, or audit workpapers.

import { getHistory } from 'ustreasury-exchange-rate';

const series = await getHistory(
  { source: 'USD', target: 'EUR', from: '2026-01-01', to: '2026-09-30' },
  { apiKey: 'art_live_...' }
);

Response:

{
  bank: 'ustreasury',
  source: 'USD',
  target: 'EUR',
  from: '2026-01-01',
  to: '2026-09-30',
  count: 152,
  rates: [
    // one entry per publication date
    { date: '2026-09-30', rate: 0.881, rate_type: 'quarterly', derived: false, method: 'published' },
    // …
  ],
  disclaimer: '…'
}

Pass { symbol: 'EUR' } instead of source/target to get the raw published rows for one currency (all rate types, no pair resolution).

---

🗺️ Currencies covered

U.S. Department of the Treasury currently publishes rates covering 145 currencies against the USD (as of the latest table):

🇦🇪 AED · 🇦🇫 AFN · 🇦🇱 ALL · 🇦🇲 AMD · 🇦🇴 AOA · 🇦🇷 ARS · 🇦🇺 AUD · 🇦🇿 AZN · 🇧🇦 BAM · 🇧🇧 BBD · 🇧🇩 BDT · 🇧🇬 BGN · 🇧🇭 BHD · 🇧🇮 BIF · 🇧🇲 BMD · 🇧🇳 BND · 🇧🇴 BOB · 🇧🇷 BRL · 🇧🇸 BSD · 🇧🇼 BWP · 🇧🇾 BYN · 🇧🇿 BZD · 🇨🇦 CAD · 🇨🇩 CDF · 🇨🇭 CHF · 🇨🇱 CLP · 🇨🇳 CNY · 🇨🇴 COP · 🇨🇷 CRC · 🇨🇺 CUC · 🇨🇺 CUP · 🇨🇻 CVE · 🇨🇿 CZK · 🇩🇯 DJF · 🇩🇰 DKK · 🇩🇴 DOP · 🇩🇿 DZD · 🇪🇬 EGP · 🇪🇷 ERN · 🇪🇹 ETB · 🇪🇺 EUR · 🇫🇯 FJD · 🇬🇧 GBP · 🇬🇪 GEL · 🇬🇭 GHS · 🇬🇲 GMD · 🇬🇳 GNF · 🇬🇹 GTQ · 🇬🇾 GYD · 🇭🇰 HKD · 🇭🇳 HNL · 🇭🇹 HTG · 🇭🇺 HUF · 🇮🇩 IDR · 🇮🇱 ILS · 🇮🇳 INR · 🇮🇶 IQD · 🇮🇷 IRR · 🇮🇸 ISK · 🇯🇲 JMD · 🇯🇴 JOD · 🇯🇵 JPY · 🇰🇪 KES · 🇰🇬 KGS · 🇰🇭 KHR · 🇰🇲 KMF · 🇰🇷 KRW · 🇰🇼 KWD · 🇰🇾 KYD · 🇰🇿 KZT · 🇱🇦 LAK · 🇱🇧 LBP · 🇱🇰 LKR · 🇱🇷 LRD · 🇱🇸 LSL · 🇱🇾 LYD · 🇲🇦 MAD · 🇲🇩 MDL · 🇲🇬 MGA · 🇲🇰 MKD · 🇲🇲 MMK · 🇲🇳 MNT · 🇲🇷 MRU · 🇲🇺 · 🇲🇻 · 🇲🇼 · 🇲🇽 · 🇲🇾 · 🇲🇿 · 🇳🇦 · 🇳🇬 · 🇳🇮 · 🇳🇴 · 🇳🇵 · 🇳🇿 · 🇴🇲 · 🇵🇪 · 🇵🇬 · 🇵🇭 · 🇵🇰 · 🇵🇱 · 🇵🇾 · 🇶🇦 · 🇷🇴 · 🇷🇸 · 🇷🇺 · 🇷🇼 · 🇸🇦 · 🇸🇧 · 🇸🇨 · 🇸🇩 · 🇸🇪 · 🇸🇬 · 🇸🇱 · 🇸🇴 · 🇸🇷 · 🇸🇸 · 🇸🇹 · 🇸🇾 · 🇸🇿 · 🇹🇭 · 🇹🇯 · 🇹🇲 · 🇹🇳 · 🇹🇴 · 🇹🇷 · 🇹🇹 · 🇹🇼 · 🇹🇿 · 🇺🇦 · 🇺🇬 · 🇺🇾 · 🇺🇿 · 🇻🇪 · 🇻🇳 · 🇻🇺 · 🇼🇸 · · · · · 🇾🇪 · 🇿🇦 · 🇿🇲 · 🇿🇼

🏛️ Source

The U.S. Department of the Treasury publishes the Treasury Reporting Rates of Exchange each quarter, through its Bureau of the Fiscal Service. Every US government agency must use these rates to convert foreign-currency balances into dollars for official reports — and contractors, grant recipients, and auditors follow the same table. Rates are amended mid-quarter when a currency moves sharply.

• Publisher's own page: Treasury Reporting Rates of Exchange · www.treasury.gov
• Publication: every quarter; the exact schedule, freshness status and any current delay are on the U.S. Department of the Treasury rates page
• Values are stored unmodified, with the publisher's own rate_date on every row — see the methodology

🧭 Reading the numbers

• value is always quote currency per 1 unit of base currency (base: "EUR", quote: "USD", value: 1.15 means 1 EUR = 1.15 USD).
• U.S. Department of the Treasury quotes foreign currency per 1 USD (e.g. base: "USD", quote: "USD" means USD per one USD).
• Need the other way round? Ask getRate(target, source) and the API inverts or crosses for you, flagged derived: true — never divide a published rate yourself in a compliance workflow.
• rate_type tells you which of the tax authority's series a row belongs to (quarterly here); some publishers print buy/sell or several fixings for the same pair.

🧩 ERP & accounting systems

Loading the official U.S. Department of the Treasury rate into an accounting system is a supported workflow, not a hack. Step-by-step guides with the direction each system expects:

• Dynamics 365 Business Central — built-in Currency Exchange Rate Service, no code
• Xero · QuickBooks Online · SAP S/4HANA and ECC · Odoo

The same keyed endpoints return ?format=csv, ?format=xml and ?format=xlsx, and accept the key as ?api_key= on the URL for importers that cannot send headers:

curl "https://allratestoday.com/api/v1/central-bank/ustreasury/latest?format=xml&api_key=art_live_..."

🤖 AI agents

• MCP server: npx -y @allratestoday/central-bank-mcp (stdio) or the hosted endpoint https://allratestoday.com/api/mcp — tools for official rates, history, cross-bank comparison and publication calendars
• Already using the general SDK or MCP server? Since 2026-10-01 @allratestoday/sdk 1.4+ has officialRates('ustreasury') and @allratestoday/mcp-server 0.6+ has a get_official_rates tool — both return this source's latest table with no key, so you can add it without a second dependency
• Claude Code plugin (no key): /plugin marketplace add AllRates-Today/claude-code-plugin then /plugin install allratestoday@allratestoday — bundles both MCP servers plus an /official-rate ustreasury ... command
• Evaluating? Agents can self-issue a trial key with no signup: POST https://allratestoday.com/api/agent/keys (send Content-Type: application/json) returns a 100-call key valid 7 days that covers the free-plan methods (latest table, pairs); dated tables and history need a paid plan. The MCP servers expose it as request_trial_key
• Machine-readable site guide: llms.txt · for-ai-agents

⚖️ Published vs derived rates

If U.S. Department of the Treasury does not print a pair directly, the API resolves it from the tax authority's own table and says so — official and computed values are never confused:

method	derived	Meaning
published	false	The tax authority printed this pair directly
inverse	true	Computed as 1 ÷ the published opposite direction
cross	true	Computed via USD from two published rates

🛡️ Error handling

Errors are thrown as Error with status (HTTP code) and body (the API's JSON error) attached:

try {
  const pair = await getRate('USD', 'XXX', { apiKey: 'art_live_...' });
} catch (err) {
  console.log(err.message); // human-readable reason
  console.log(err.status);  // e.g. 404
}

Status	Meaning
—	Missing apiKey (thrown before any request)
400	Malformed date or parameters
401	Invalid API key
403	Endpoint needs a paid plan (historical dates & series)
404	Pair or date range not covered by U.S. Department of the Treasury
429	Monthly quota exceeded

🔷 TypeScript

Full definitions ship with the package — no @types install:

import type { LatestRates, PairRate, DatedRates, RateEntry, HistoryQuery, RequestOptions } from 'ustreasury-exchange-rate';

📦 CommonJS

const { getRate } = require('ustreasury-exchange-rate');

getRate('USD', 'EUR', { apiKey: 'art_live_...' }).then((pair) => console.log(pair.rate));

💡 Quota tips

• Rates change once a quarter — cache the published table locally and a small monthly quota goes a long way.
• Every request counts toward your AllRatesToday quota, shared across all AllRatesToday endpoints on your key.

📖 Methods reference

Method	Plan	Description
getRate(source, target, { apiKey })	Free	Latest rate for one pair, resolved from the published table
getLatestRates({ apiKey })	Free	The tax authority's full latest published table
getRatesForDate(date, { apiKey, source?, target? })	Paid	The official table (or one pair) for a YYYY-MM-DD date
getHistory({ symbol | source+target, from?, to? }, { apiKey })	Paid	Daily series since 2001

📥 Bulk data (no key)

Need the whole archive rather than an API call? The same published tables are mirrored daily as open data:

• Hugging Face: AllRatesToday/central-bank-exchange-rates — one CSV per institution (rates/ustreasury.csv)
• Kaggle: allratestoday/central-bank-exchange-rates
• Raw JSON on GitHub: https://raw.githubusercontent.com/AllRates-Today/central-bank-exchange-rates/main/data/ustreasury/latest.json

🔗 Links

• Website: allratestoday.com
• U.S. Department of the Treasury rates page — live table, publication cadence, FAQ
• All tax authority sources
• Download central bank rates — every bank's latest table and history as Excel, CSV or JSON
• Package docs on the site · ERP integration guides
• API documentation · Interactive reference · Methodology
• Register (Free) · Dashboard · Pricing
• Status
• Postman collection
• ChatGPT app — ask ChatGPT for live and official central bank rates
• GitHub

📜 License

MIT