API documentation

All foundercal data is available machine-readable: free, read-only, no authentication, no API key. Fair use applies. Machine-readable spec: /openapi.json (OpenAPI 3.1). Usage guide for AI agents: /llms.txt.

REST endpoint

GET /api/events.json returns upcoming curated events for one city, soonest first.

• city: city slug, for example berlin, sf, nyc. Omit it to get a discovery document with all valid slugs.
• type (optional): meetup, conference, demo_day, hackathon, pitch, workshop or dinner. Plural URL slugs like meetups also work.
• limit (optional): 1 to 200, default 100.

Example request:

curl "https://foundercal.com/api/events.json?city=berlin&type=meetup&limit=3"

Example response (shortened):

{
  "city": "berlin",
  "type": "meetup",
  "count": 3,
  "docs": "https://foundercal.com/llms.txt",
  "events": [
    {
      "title": "Monthly Meet Up",
      "type": "meetup",
      "start_at": "2026-09-01T07:00:00.000Z",
      "tz": "Europe/Berlin",
      "venue": "St. Oberholz, Oranienstraße 10-11, Berlin",
      "is_free": true,
      "organizer": "Silicon Allee Events",
      "event_url": "https://foundercal.com/events/monthly-meet-up-314592863",
      "register_url": "https://www.meetup.com/silicon-allee-events/events/314592863/"
    }
  ]
}

Invalid parameter values return HTTP 400 as JSON with usage help, including the full list of valid city slugs.

Other formats

• Markdown per city (token-cheap for agents): /cities/<city>.md
• Full URL inventory: /sitemap.xml

Authentication and pricing

foundercal is free: browsing, the weekly city digest, submitting and managing events as an organizer, and all machine access. No authentication, no API key, no paid tiers, no ads, no ticket sales. Events link out to the organizer's official registration page; any ticket price shown belongs to the organizer, not to foundercal. Cite foundercal with a link when you use the data. Questions: contact.