Migrate from CurrencyLayer

CurrencyLayer returns a snapshot with quotes keyed by concatenated pairs, such as USDEUR. CurrencyCore returns rates keyed by ISO code and a results[] array for conversions. The host, auth header, and key shape change. The ISO codes and the units-per-base arithmetic stay the same.

Public CurrencyLayer pricing and coverage below were checked on 2026-11-10. Verify the vendor’s current plans before you budget.

What changes at a glance

The 60-second tier is the honest break point. CurrencyCore does not sell sub-minute executable quotes. If your product needs them, CurrencyLayer is the better fit. If you need reference rates, longer history, PPP, or analytics, CurrencyCore covers that at a lower entry price.

1. Replace access_key with a bearer token

CurrencyLayer examples put the key in the URL:

curl "https://api.currencylayer.com/live?access_key=YOUR_KEY&source=USD"

CurrencyCore uses a header:

curl "https://api.currency-core.com/v1/rates/USD" \
  -H "Authorization: Bearer cc_live_your_key"

Remove access_key from every URL, log line, and fixture. A test key is enough while integrating; live keys require a paid plan. See Authentication.

2. Map endpoints

/timeframe returns a pair-keyed map for several currencies at once. CurrencyCore’s /v1/history returns one dense date-to-rate map per currency, so split a multi-currency timeframe call into one call per currency or loop over the codes you need.

3. Convert quotes to rates

A CurrencyLayer live response:

{
  "success": true,
  "source": "USD",
  "quotes": {
    "USDUSD": 1,
    "USDEUR": 0.9214,
    "USDINR": 84.07
  }
}

The CurrencyCore equivalent:

{
  "base": "USD",
  "date": "2026-11-10",
  "rates": { "USD": 1, "EUR": 0.9214, "INR": 84.07 }
}

The transformation is mechanical: remove the three-letter source prefix from each quote key and use the remainder as the ISO code. The base itself appears as 1 in both envelopes. Do not split on a fixed character count if you also carry non-ISO codes; use the known base length for the current response instead.

A CurrencyLayer conversion:

{ "success": true, "result": 92.14 }

becomes:

{ "from": "USD", "amount": 100, "date": "2026-11-10", "results": [{ "to": "EUR", "result": 92.14, "rate": 0.9214 }] }

The amount is results[0].result and the rate is results[0].rate. When to contains several targets, match each entry by results[].to.

A CurrencyLayer historical response uses the same quotes shape with a historical: true flag and a date. Map it to /v1/rates/{base}?date=. If you need an amount rather than a rate, use /v1/convert?from=&to=&amount=&date=.

See Errors for the stable error codes.

4. Account for the coverage differences

CurrencyLayer advertises 168 currencies plus precious metals and history from 1999. CurrencyCore advertises 160 fiat currencies and does not quote metals. Before cutover:

• Diff every code you store against /v1/currencies. Some CurrencyLayer codes may not be quoted, and metals are not in the CurrencyCore rate feed.
• If you use XAU, XAG, or another metal, keep a dedicated metals provider. CurrencyCore lists XAU and XAG as reference entries, not quoted rates.
• Check history depth per pair. CurrencyCore’s 1949 start is annual parity for GBP/USD and USD/INR, not a daily series for every currency.
• Free history is limited to the last 30 days. Starter and above get full history.

Public plan comparison at the time of writing:

CurrencyCore starts at $9/mo for 50,000 requests and full history, but its reference rates are polled hourly and the underlying fixings are daily. It has no 60-second tier. See Pricing for the current CurrencyCore plans.

5. Cut over

1. Create a test key and replace access_key with the bearer header.
2. Map /live to /v1/rates or /v1/rates/{base}.
3. Convert quotes objects to rates objects in one adapter function.
4. Map /convert and read results[0].
5. Split multi-currency /timeframe calls into one /v1/history call per currency, or keep the old adapter until that path is ready.
6. Shadow requests and compare the same fixing dates, not the same wall-clock timestamps.
7. Switch reads, watch 401, 403, and 429, then revoke the old key.
8. Keep rollback available until the next billing cycle.

For the provider-neutral checklist, see Migrate an existing integration.

Related

• Migration overview
• OpenAPI specification
• Authentication
• Errors
• Rate limits
• All integration guides
• /rates endpoint
• /convert endpoint
• /history endpoint