Trade and Development Bank of Mongolia Exchange Rate API: MNT Buy and Sell Rates as JSON

Trade and Development Bank (TDB) is one of Mongolia’s largest commercial banks, headquartered in Ulaanbaatar. Its exchange-rates page lists non-cash and cash buying and selling rates against the tugrik for about 17 currencies, with the Bank of Mongolia rate alongside. This guide shows how to read that board as JSON: what the rates mean, how they compare with the Bank of Mongolia official rate and with other banks in Mongolia, and the calls that return them.

What the TDB board shows

• 17 currencies against the Mongolian tugrik: AUD, CAD, CHF, CNY, EUR, GBP, HKD, INR, JPY, KRW, NZD, RUB, SEK, SGD, THB, TRY and USD. Every value is MNT per 1 unit of the foreign currency.
• The non-cash pair. Mongolian banks print separate cash and non-cash buying and selling rates against the tugrik for a dozen or more currencies, with the Bank of Mongolia rate alongside. The non-cash US dollar spread is usually around 0.3%, and cash spreads are wider. The Bank of Mongolia official rate is shown next to each row.
• USD on 15 November 2026: TDB bought at 3596 and sold at 3604 MNT, a spread of 0.22%. The Bank of Mongolia official rate was 3603.46, so the bank's mid sat -0.10% from it.
• No timestamp on the bank's page. TDB does not print a last-updated time, so bank_updated_at is null and captured_at (when AllRatesToday read the page) is the only time available.
• Every day's board is kept permanently, from 15 November 2026, the day collection started. Read one past day with ?date=, or a range for one currency with the /history endpoint (paid plans).

Spreads across the board

On the 15 November 2026 board the tightest spreads were USD (0.22%), HKD (0.65%), CNY (0.74%) and the widest RUB (15.04%), SEK (5.01%), THB (4.32%). Spread is (sell − buy) ÷ mid: what a round trip through the bank costs, before any fees. The API returns it on every row as spread_pct, so you can rank currencies or alert when a bank widens its board.

USD at TDB and other banks in Mongolia

USD on the 8 boards AllRatesToday reads in Mongolia, all captured on 15 November 2026 (the Bank of Mongolia official rate was 3603.46):

TDB had the 5th narrowest USD spread of the 8. One call to /api/v1/bank-rates/mn returns every board in the table at once.

Get the board (REST)

You need an API key; the free key works. The full board:

curl "https://allratestoday.com/api/v1/bank-rates/mn/tdbm" \
  -H "Authorization: Bearer art_live_your_key"

What comes back (the 15 November 2026 board, first three rows):

{
  "bank": "tdbm",
  "name": "Trade and Development Bank of Mongolia",
  "country": "mn",
  "quote_ccy": "MNT",
  "bank_updated_at": null,
  "basis": "Non-cash",
  "captured_at": "2026-11-15T03:58:35.483Z",
  "rates": [
    {"ccy":"AUD","buy":2408,"sell":2485,"mid":2446.5,"spread_pct":3.147,"official":2447.83,"vs_official_pct":-0.054},
    {"ccy":"CAD","buy":2504,"sell":2545,"mid":2524.5,"spread_pct":1.624,"official":2527.24,"vs_official_pct":-0.108},
    {"ccy":"CHF","buy":4245,"sell":4358,"mid":4301.5,"spread_pct":2.627,"official":4312.16,"vs_official_pct":-0.247},
    … 14 more currencies
  ],
  "disclaimer": "…",
  "attribution": { … }
}

One currency, with the row fields at the top level:

curl "https://allratestoday.com/api/v1/bank-rates/mn/tdbm?ccy=USD" \
  -H "Authorization: Bearer art_live_your_key"

{
  "bank": "tdbm",
  "name": "Trade and Development Bank of Mongolia",
  "country": "mn",
  "quote_ccy": "MNT",
  "bank_updated_at": null,
  "basis": "Non-cash",
  "captured_at": "2026-11-15T03:58:35.483Z",
  "ccy": "USD",
  "buy": 3596,
  "sell": 3604,
  "mid": 3600,
  "spread_pct": 0.222,
  "official": 3603.46,
  "vs_official_pct": -0.096,
  "disclaimer": "Retail buy/sell rates as displayed on each bank’s own website at capture time, quoted as home currency per 1 unit of foreign currency. Indicative only: banks change these through the day, apply them at the counter or in-app, and they are not official or reference rates. For the rate a regulation names, use the central-bank endpoints.",
  "attribution": {
    "source": "Board rates published by Trade and Development Bank of Mongolia on its own website, collected by AllRatesToday",
    "bank_url": "https://www.tdbm.mn/mn/exchange-rates",
    "url": "https://allratestoday.com/bank-exchange-rate-api/mn/tdbm/",
    "terms": "Public pages that show the rates need a visible link to allratestoday.com"
  }
}

The board as it stood on a past day:

curl "https://allratestoday.com/api/v1/bank-rates/mn/tdbm?date=2026-11-15" \
  -H "Authorization: Bearer art_live_your_key"

One currency over a date range, one row per day (paid plans; add &format=csv, xml or xlsx for a file):

curl "https://allratestoday.com/api/v1/bank-rates/mn/tdbm/history?ccy=USD&from=2026-11-15&to=2026-11-15" \
  -H "Authorization: Bearer art_live_your_key"

JavaScript

npm install @allratestoday/sdk

import { AllRatesToday } from '@allratestoday/sdk';

const client = new AllRatesToday({ apiKey: 'art_live_your_key' });

// Trade and Development Bank of Mongolia's USD row
const r = await client.bankRates('mn', { bank: 'tdbm', ccy: 'USD' });
console.log(`TDB buys USD at ${r.buy}, sells at ${r.sell} MNT`);

// The board as it stood on a past day
const past = await client.bankRates('mn', { bank: 'tdbm', date: '2026-11-15' });
console.log(past.snapshot_date, past.rates.length);

Python

import requests

r = requests.get(
    "https://allratestoday.com/api/v1/bank-rates/mn/tdbm",
    headers={"Authorization": "Bearer art_live_your_key"},
    timeout=10,
)
r.raise_for_status()
for row in r.json()["rates"]:
    print(row["ccy"], row["buy"], row["sell"], row["spread_pct"])

Board rate or official rate?

The Bank of Mongolia rate is the one tax, accounting and customs rules in Mongolia name; nobody transacts at it. TDB's board is the price a customer actually gets. The API puts both on every row: official is the central bank's rate for the same currency and vs_official_pct is how far the bank's mid sits from it. Use the board to show customers a real price, compare banks for a remittance, or keep a dated record of what the bank quoted; use the Bank of Mongolia endpoint when a rule asks for the official rate.

FAQ

Where do the Trade and Development Bank of Mongolia rates come from?

From the bank's own public rates page (https://www.tdbm.mn/mn/exchange-rates), read hourly. AllRatesToday does not change the numbers: each row is the buy and sell price TDB shows, with the mid, the spread and the Bank of Mongolia rate added.

Are these the official MNT exchange rates?

No. They are TDB's retail prices for customers. The official rate in Mongolia is the Bank of Mongolia rate, which the API returns as official on each row where the central bank has one, and in full from the central-bank endpoint.

How often is the TDB board updated?

AllRatesToday reads the page every hour. The bank prints no timestamp, so captured_at tells you when the rates were read.

Can I get TDB rates for a past date?

Yes, from 15 November 2026 onward; every day's board is kept permanently. Add ?date=YYYY-MM-DD for one day: the response is the board captured that day, or the nearest earlier day within five days, with date_requested and snapshot_date added. For a range, /history?ccy=USD&from=…&to=… returns one row per day as JSON, CSV, XML or XLSX on paid plans.

Do I need an API key?

Yes. Commercial bank boards need an API key; any plan works, the free key included, and each call counts against the plan. Public pages or widgets that show the rates need a visible link to allratestoday.com.