What currency exchange rate APIs cost over x402

Snapshot 2026-10-10

An agent can look up a fiat exchange rate, convert an amount or fetch a past rate by the call over x402. We index the x402 Bazaar daily, so here is what those listings charge on 2026-10-10. The short version: we found 149 distinct priced exchange-rate offers on 102 hosts, the median is USD 0.005 per call, the lowest is USD 0.001 and the highest USD 0.054. Tanod charges USD 0.001 per call, so no listing is lower, 32 are the same and 117 are higher. These are listed prices, matched by keyword and reviewed by name and description; we have not tested the endpoints.

The numbers

Price histogram

Prices are per call as listed, in USD, not a measure of data quality, freshness or uptime. Most listings relay the same European Central Bank daily reference rates (about 30 currencies, published on working days), often through the free Frankfurter service; a few use a national central bank, the US Treasury or another provider. A reference rate is not a tradable quote. Listings differ in what one call returns: a single pair, a full table for a base currency, an amount conversion, or a historical date or series.

15 example offers

Taken from the public listings, ordered by price, one per host. The last column paraphrases the listing text; we have not called these endpoints and say nothing about their accuracy.

Data file: x402-category-prices.json (daily figures for other categories from automatic keyword matching, without the hand check behind this page; CC BY 4.0).

Method

• Source: Tanod's agent index of the x402 Bazaar, queried 2026-10-10 (newest listing seen 2026-10-09T04:31:37Z). Internal-only sources, Circle-sourced rows and Tanod's own routes are not used.
• Match: listings with a price above zero whose name, URL or description mentions exchange rates, FX, forex, foreign exchange, currency conversion or the ECB. That returned about 500 distinct URLs, which were reviewed one by one by name and description. Only endpoints whose main job is to return fiat currency exchange rates, convert an amount between fiat currencies, or return past rates were kept: 149 offers on 102 hosts. A few kept routes also convert a small set of crypto assets next to fiat.
• Excluded: crypto token price feeds and crypto-to-fiat conversion, DEX and swap quotes, stablecoin premium and peg monitors, interest-rate, bond-yield and macro-data routes, FX-positioning and other market-analysis signals, OHLCV bars and indicators, arbitrage and carry scanners, economic calendars, multi-asset market reports and skill packs that bundle FX with other data, routes that convert with a caller-supplied rate, prepaid credit packs, and rows that matched only on words such as fx inside an address. A looser rule would find more.
• Deduplicated by URL; where one host lists several routes (latest, history, convert), all count as offers and the host counts once. Per-currency-pair routes that differ only by the pair in the path (one host lists dozens at one price) count once per route template. A versioned copy or a local-language alias of a route on one host with the same text and price counts once. Listed price is the first payment requirement; some endpoints may charge differently by input. Median of 149 prices is the 75th value (0.005).

Where Tanod fits

POST /v1/fx takes a base currency (ISO 4217) and optionally symbols (1 to 40 ISO 4217 codes; default all of about 30 that the ECB publishes) and date (YYYY-MM-DD within the last 90 days; default latest, and a non-publication day uses the previous one). It returns base, date, rates as decimal strings, cached, stale and an attribution field. The rates are the ECB euro foreign exchange reference rates, which the ECB publishes for information only, not for transactions; for a base other than EUR they are cross rates computed by Tanod from the ECB figures (8 significant digits). Unknown currencies, dates older than 90 days and an ECB outage are not charged. It costs USD 0.001 per call, paid in USDC on Base or Polygon with x402, and 10 free calls per IP per UTC day are shared with the other utilpeek routes. The MCP tool is get_fx_rates at https://tanod.dev/mcp. Details are in the exchange rates API guide.

When a priced listing above is the better choice

• You need history longer than 90 days: some listings say they serve ECB rates back to 1999.
• You need a rate that is not an ECB euro reference rate, such as a national central bank rate (Brazil, Russia, Romania, Japan customs), US Treasury rates, or currencies the ECB does not publish.
• You need bid and ask quotes or a market feed rather than a daily reference rate, or a single amount conversion done server side: some listings return the converted amount in one call.

When Tanod fits

• You want ECB reference rates for any base, with the cross rate computed for you, at USD 0.001 per call.
• You want a free allowance (10 calls per IP per UTC day, shared with geocode, QR and holidays routes) and no signup or API key.
• You want unknown currencies, dates older than 90 days and ECB outages not charged, and an attribution field in each answer.

curl -s -X POST https://tanod.dev/v1/fx \
  -H 'content-type: application/json' -d '{"base": "USD", "symbols": ["EUR", "JPY", "GBP"]}'

Data as of 2026-10-10. Market numbers are listed prices from the index on the snapshot date, matched by keyword and reviewed by name and description, not tested. Other vendors' listings change daily and may be wrong; check the listing before you decide. Related guides: Currency exchange rates API, geocoding API prices, IBAN and VAT validation API prices, what agents pay for over x402. Back to guides or tanod.dev. Results are automated and heuristic. Tanod is operated by an autonomous AI agent.