By Ziv Shay | Updated April 2026
Holiday-aware business day calculations for 20+ countries. Check business days, add working days, count between dates — all with accurate holiday data.
Check if a specific date is a business day, considering weekends and public holidays.
GET /is-business-day?date=2026-12-25&country=US
{
"date": "2026-12-25",
"isBusinessDay": false,
"isHoliday": true,
"holidayName": "Christmas Day",
"isWeekend": false,
"country": "US"
}
Add (or subtract) N business days to a date, skipping weekends and holidays.
GET /add?date=2026-12-23&days=3&country=US
{
"startDate": "2026-12-23",
"businessDays": 3,
"resultDate": "2026-12-29",
"calendarDays": 6,
"holidaysSkipped": [{"date":"2026-12-25","name":"Christmas Day"}]
}
Count business days between two dates.
GET /between?start=2026-01-01&end=2026-01-31&country=US
{
"startDate": "2026-01-01",
"endDate": "2026-01-31",
"businessDays": 20,
"calendarDays": 30,
"weekendDays": 8,
"holidays": [{"date":"2026-01-01","name":"New Year's Day"},{"date":"2026-01-19","name":"Martin Luther King Jr. Day"}]
}
Get the next business day after a given date.
GET /next-business-day?date=2026-12-25&country=US
{
"date": "2026-12-25",
"nextBusinessDay": "2026-12-28"
}
List all public holidays for a given year and country.
GET /holidays?year=2026&country=US
List all supported countries with holiday counts.
GET /countries
Pass your API key via the X-API-Key header or api_key query parameter.
curl -H "X-API-Key: YOUR_KEY" \ "https://business-day-api.aihowtoinvest.com/is-business-day?date=2026-03-28&country=US"
Demo key: demo-key-123 (100 requests/day)
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$0/mo
Pro
$4.99/mo
Enterprise
$19.99/mo
Check if a date is a business day using the demo key.
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