Calendar API

A free, read-only JSON API for name days, holidays, flag days, moon phase, and week numbers. No key, no sign-up. Each host answers for its own calendar.

https://nordiccalendar.app/api/v1

Endpoints

GET /api/v1/today
Everything about today.
GET /api/v1/date/2026-12-06
A specific date in YYYY-MM-DD form.
GET /api/v1/name-day/Anna
When a given name is celebrated, this year and next.

Response fields

date: ISO date, YYYY-MM-DD.
weekday: Weekday name in the local language.
weekNumber: ISO 8601 week number, 1 to 53.
nameDay: Names celebrated that day.
holidays: Public holidays, each with a name and slug.
flagDays: Official flag days, each with a name and slug.
moon: Moon phase and illuminated fraction.

Example response

Live response from this calendar today:

{
  "locale": "en",
  "date": "2026-06-13",
  "weekday": "Saturday",
  "weekNumber": 24,
  "nameDay": {
    "names": [
      "Raili",
      "Raila"
    ]
  },
  "holidays": [],
  "flagDays": [],
  "moon": {
    "phase": "waningCrescent",
    "illumination": 0.07
  }
}

Rate limit

Up to 60 requests per minute per IP. Responses cache for an hour, so most apps never reach the cap. Over the limit returns 429 with a Retry-After header.

Terms

Use it for free in apps, sites, and side projects. A link back to Nordic Calendar is welcome but not required. Data can change, so treat each response as a snapshot.