Every calendar.
One API.

Events, free time and sync for nine providers, including Google, Outlook and iCloud, in one typed TypeScript API.

Get started
Nov 9 – 13November 9 – 13, 2026New York time
Calendars
Day
    Pick an event to see what calsdk returns.

    Running in your browser: six sample calendars in memory, with the real listEvents, findFreeTime and createEvent.

    Switch calendars, not code

    Pick a provider. Only the import and the setup change, and the events come back in the same shape.

    Choose a provider
    import { listEvents } from 'calsdk';
import { google } from '@calsdk/google';

const calendar = google({ accessToken });

const { events } = await listEvents({
  calendar,
  timeMin: '2026-11-01T00:00:00Z',
  timeMax: '2026-12-01T00:00:00Z',
});

for (const event of events) {
  console.log(
    event.title,
    event.start,
    event.conference?.joinUrl,
  );
}
    • Read, supported
    • Write, supported
    • Recurring, supported
    • Video linksGoogle Meet
    • Sync, supported

    The quirks are handled.The rest is reported.

    Recurrence, time zones and field names are converted for you. When a provider can't do what you asked, the result says so.

    How warnings work
    "pattern": {
  "type": "weekly",
  "daysOfWeek": ["monday",
    "tuesday", "wednesday",
    "thursday", "friday"]
}

    'RRULE:FREQ=WEEKLY;BYDAY=MO,TU,WE,TH,FR'

    Recurrence is always an RRULE

    Outlook stores a pattern object and Zoom numbers its weekdays. You read and write one RRULE.

    color: '#ec4899'

    #ec4899 asked#e67c73 saved

    warnings: [{ type: 'compatibility', feature: 'color' }]

    Warnings, not silent changes

    Google has a fixed palette. Your color is saved as the nearest one, and the result says so.

    9:30 New York standup, in Berlin, March 2027

    Mon, Mar 815:30
    Mon, Mar 1514:30
    Mon, Mar 2214:30
    Mon, Mar 2915:30

    Time zones that survive clock changes

    The standup stays at 9:30 in New York. Berlin sees it an hour early until Europe changes its clocks too.

    The calendar code you'd rather not write

    Read the guides

    Book a meeting, with the video link

    Create a meeting with a Google Meet or Teams link. Provider changes come back as warnings.

    import { createEvent } from 'calsdk';

const result = await createEvent({
  calendar,
  event: {
    title: 'Intro call',
    start: {
      dateTime: '2026-11-12T15:00:00',
      timeZone: 'Europe/Berlin',
    },
    end: {
      dateTime: '2026-11-12T15:30:00',
      timeZone: 'Europe/Berlin',
    },
    attendees: [
      { email: 'guest@example.com' },
    ],
    createConference: true,
  },
  sendUpdates: 'all',
});
    // result.event.conference
{
  provider: 'google-meet',
  joinUrl:
    'https://meet.google.com/…',
  id: '…',
}

// result.warnings
[]

    Runs anywhere

    Only fetch, no vendor SDKs. Node, Bun, Deno and edge runtimes.

    A calendar for tests

    @calsdk/mock keeps a real calendar in memory. The demo at the top runs on it.

    Tested on the real APIs

    Google, Outlook, Zoho, Zoom, Cal.com and Calendly are recorded live and replayed in CI.

    Bring your own provider

    A provider is one object with a few functions, checked by the conformance suite.

    Try it without connecting a calendar

    Read the quickstart