fx.reference_rate

ECB Reference Rate

The European Central Bank euro reference rate for a pair: the latest published fix or any date in the last 90 days. Inverse and cross rates are computed from the same fix and named as such.

Example answer

Ask

What is the ECB reference rate for EUR to USD?

GET /v1/fx/reference-rate?base=EUR&quote=USD

Eckari

{
  "base": "EUR",
  "quote": "USD",
  "rate": "1.157600",
  "rate_date": "2026-08-18",
  "rate_kind": "reference",
  "rate_derivation": "published",
  "published_pairs_used": [
    "EUR/USD"
  ]
}

Source: European Central Bank
Freshness: Near live
Price: $0.002

Version: 2.1.0
Transport: HTTP / MCP
Coverage: Global

Use this when

Convert or report an amount at an official daily rate both sides of a contract can verify against the ECB.
What is the ECB reference rate for EUR to USD?
You need the rate to put on an invoice, a ledger entry or a statutory report.
You need an official, auditable daily reference rate for reporting or accounting.
You need a historical reference rate from the last 90 days.
You need a cross rate such as GBP to USD derived from the ECB euro fix.

Don't use this when

You need an executable, tradable, live or intraday market rate - this is a daily fix only.
You need cryptocurrency prices - not supported.
You need rates older than 90 days - not supported.
You need a currency the ECB does not publish (returns INVALID_INPUT).

If the user has asked you to inspect a specific website, page or URL, use your browsing tool instead — this capability only returns the ECB euro foreign exchange reference rates record.

Input

basestringrequired

ISO 4217 code of the base currency. EUR is always available; other currencies must be in the ECB reference rate list for the selected date.

quotestringrequired

ISO 4217 code of the quote currency. EUR is always available; other currencies must be in the ECB reference rate list for the selected date.

datestringoptional

Optional ISO calendar date (YYYY-MM-DD) within the last 90 days. When the ECB published no fix on that date (a TARGET closing day), the latest prior fix is returned with a note.

What the result means

basestring

Base currency (ISO 4217, upper case).

quotestring

Quote currency (ISO 4217, upper case).

ratestring

Units of quote currency per 1 unit of base currency, as a decimal string with 6 decimal places. Computed with exact integer arithmetic from the ECB fix (rate = published(quote) / published(base), with EUR = 1) and rounded half-even - never floating point. Unless rate_derivation is published, this is a computed value rather than a figure published by the ECB, and rounding means it need not round-trip exactly against the published fix.

rate_datestring

TARGET working day of the ECB fix used (the Cube time value), which may be earlier than a requested date or than today when no fix has been published yet - see note.

rate_kindstring

Always the string reference - an official daily reference rate, not a tradable or executable market rate.

rate_derivationstring

How the rate relates to what the ECB publishes. published = the ECB EUR/quote fix itself (base EUR); inverse = 1 divided by the EUR/base fix (quote EUR), an Eckari computation; cross = the EUR/quote fix divided by the EUR/base fix, an Eckari computation from two published quotations of the same fix (neither side EUR); identity = EUR to EUR (1). Only published values are ECB figures.

Provenance

Source: European Central Bank
Freshness: Near live · cache shared · up to 3600s
Region: Global

Access

Over MCP: fx_reference_rate
Over HTTP: GET https://api.eckari.com/v1/fx/reference-rate
Price: $0.002 per call over x402. Account access $0.0015 when that rail opens.