Scheduling API for platforms

Add scheduling to your product.
Skip the edge cases.

One REST API handles availability, bookings, calendar sync, time zones, reminders, and webhooks. Your users get a seamless scheduling experience. Your engineers stay focused on your product.

Read the docsSee the API
terminal
$ curl -X POST \
  https://www.kalendme.com/api/v1/users \
  -H "Authorization: Bearer km_key" \
  -H "Content-Type: application/json" \
  -d '{
    "email": "dr.silva@yourapp.com",
    "name": "Dr. Silva",
    "timezone": "America/Sao_Paulo"
  }'
Why not build it?

Every team thinks scheduling is a weekend project

Then they discover what it actually takes.

Time zone math

DST transitions, IANA database updates, users across 20+ zones. One missed edge case means missed appointments.

Calendar sync that breaks

Google and Microsoft OAuth tokens expire. Webhooks go silent. Rate limits change. You become a calendar maintenance team.

Availability is a constraint problem

Overlapping events, buffer time, multi-host conflicts, recurring exceptions. It is not a query. It is an engine.

The backlog never ends

Rescheduling, cancellations, reminders, no-show handling, round-robin fairness. Every feature spawns three more.

KalendMe solved these problems over five years and 1.4 million calendar events. You get the result in one API call.

API capabilities

Everything your product needs to schedule

Booking links

Create scheduling links per user with custom duration, availability windows, location, and buffer time.

POST /v1/users/{userId}/links

Real-time availability

Query open slots for any user, any link, any date range. Factors in all connected calendars and buffer time.

GET /v1/users/{userId}/links/{linkId}/availability

Calendar sync

Two-way sync with Google Calendar, Microsoft Outlook, and Office 365. Push notifications keep everything current.

GET /v1/users/{userId}/calendars

Round-robin & groups

Distribute bookings across team members automatically, or require all hosts for group meetings.

schedulingMode: ROUND_ROBIN

Webhooks

Get notified on event creation, cancellation, and reservation expiry. Full delivery logs included.

POST /v1/webhooks

Mass availability

Find time slots where multiple users are all free. One call replaces hundreds of individual checks.

POST /v1/availability/calculate-mass-availability
Integration

Three API calls to your first booking

1

Create a user

Map your platform users to KalendMe. Each gets their own calendar, availability, and booking links.

request
POST /v1/users
{
  "email": "dr.silva@yourapp.com",
  "name": "Dr. Silva",
  "timezone": "America/Sao_Paulo"
}
2

Create a booking link

Configure duration, availability hours, buffer time, and location. Embed the booking page or build your own UI.

request
POST /v1/users/{userId}/links
{
  "title": "Consultation",
  "durationMinutes": 50,
  "schedulingMode": "SOLO"
}
3

Receive bookings

Your backend gets notified. Calendar events sync automatically. Confirmation emails are sent. Zero scheduling code.

request
// Webhook payload
{
  "event": "event.created",
  "data": {
    "title": "Consultation",
    "status": "CONFIRMED",
    "attendees": [{ "name": "Maria" }]
  }
}
In production

Trusted by platforms across Latin America

1.4M+

Calendar events processed

3,500+

Users on the platform

5 yrs

In production

“We mapped the edge cases — timezone DST, token refresh, recurrence rules, multi-host conflicts — and realized it was not a project with an end date. It was a permanent engineering commitment. We would rather our team works on what makes us different.”

CTO, Y Combinator-backed mental health platform

Pricing

Pay per booking, not per seat

Your platform grows, your costs stay predictable. No per-user charges for API customers.

Sandbox

Test everything. No limits.

Free
  • Full API access
  • Test environment
  • Webhook testing
  • No credit card
Start building

Launch

First 100 bookings free.

$0/mo
  • 100 bookings/mo included
  • Calendar sync
  • Email notifications
  • $0.25 per extra booking
Start building

Grow

For growing platforms.

$99/mo
  • 500 bookings/mo included
  • Round-robin & groups
  • Mass availability API
  • $0.15 per extra booking
  • Priority support
Start building

Scale

For scaled platforms.

$499/mo
  • 2,000 bookings/mo included
  • Everything in Grow
  • $0.10 per extra booking
  • Dedicated support
  • Custom SLA
Talk to us

Need more? Enterprise plans with custom pricing, SLA, and white-label options. Contact us

Developer experience

Built for developers who ship fast

REST API, no SDK required

Standard JSON over HTTPS. Auth via API key in the Authorization header. Works with any language, any framework.

MCP server for AI agents

Published on npm as @kalendme/mcp-server. Let AI assistants check availability, book meetings, and manage schedules.

Webhooks with delivery logs

Register endpoints, choose events, inspect delivery history. Debug without guessing.

Comparison

How KalendMe compares

Time to first booking

KalendMeHours
Build in-houseMonths
CalendlyN/A
Cronofy / NylasWeeks

Calendar sync

KalendMeIncluded
Build in-houseYou build it
CalendlyTheir UI only
Cronofy / NylasIncluded

Booking UI

KalendMeHosted + API
Build in-houseYou build it
CalendlyTheir UI only
Cronofy / NylasAPI only

Round-robin

KalendMeIncluded
Build in-houseYou build it
CalendlyEnterprise $$$
Cronofy / NylasLimited

Pricing model

KalendMePer booking
Build in-houseEng. salary
CalendlyPer seat $10+
Cronofy / NylasPer user $3-9

LATAM-native

KalendMePT/ES/EN, BRL
Build in-house—
CalendlyEnglish-first
Cronofy / NylasEnglish-first
FAQ

Common questions

Your product needs scheduling.
You don't need to build it.

Read the docsTalk to us