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post/holidays/v1/is_workday1 credit

is a given date a working day for a country? (weekend + public-holiday aware; reasons[] explain)

Working example
Parameters

2-letter ISO-3166 country code (e.g. US, GB, DE, TR, JP). 123 countries supported — call action='countries' for the full set. Case-insensitive.

The date to test, in ISO format YYYY-MM-DD.

Override the weekend definition with day names (e.g. 'Sat,Sun' or 'Fri,Sat'). Defaults to Sat+Sun (Fri+Sat for EG/BD).

Which holiday types count as a day off (comma-separated, case-insensitive). Defaults to Public only.

Optional ISO-3166-2 subdivision code (e.g. US-CA, GB-SCT) for region-precise business days. Omit for nationwide. Case-insensitive.

request preview
curl -X POST https://api.reefapi.com/holidays/v1/is_workday \
  -H "x-api-key: $REEF_KEY" \
  -H "content-type: application/json" \
  -d '{"country":"US","date":"2026-01-01"}'

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