Build powerful custom apps with Calendly APIs

Calendly’s APIs let developers embed scheduling into tools, workflows, and products without the heavy lifting.

From syncing event data and triggering workflows with webhooks to booking meetings through the Scheduling API, you can build smarter scheduling experiences that fit your users’ needs.

Today, Calendly’s API platform includes:

• Scheduling API

• API v2

• Webhooks

• JavaScript embed

Let’s walk through what you can do with each one.

Scheduling API

The Scheduling API makes it possible to create new Calendly events programmatically. Using the Create Event Invitee endpoint, your users can book meetings on behalf of their invitees directly from your apps and workflows — no redirects, iframes, or Calendly UI required.

Here’s how the Scheduling API works behind the scenes:

• Invitee details, time selection, and custom questions are captured through the API

• Calendly completes the booking just like any other event

• Standard Calendly actions — like calendar invites, reminders, Workflows, and notifications — are automatically triggered

The Scheduling API lets you build booking flows that feel fully native but are powered by Calendly’s scheduling infrastructure. Unlock AI-powered scheduling use cases like AI agents, workflow automations, and more.

Note: Calendly users must be on a paid plan to access or use applications with the Scheduling API.

Build AI-powered scheduling experiences

With the Scheduling API, you can empower AI voice agents, texting or SMS platforms, chatbots, or other AI assistants to suggest times and book meetings on behalf of your users’ invitees.

The Scheduling API makes it possible to build apps and integrations that:

• Connect Calendly scheduling to AI chatbots, voice agents, sales assistants, and more.

• Reduce end-user scheduling drop-offs by handling the full booking flow within the AI interaction.

• Maintain all the benefits of Calendly’s platform, like automated reminders, calendar invites, and workflows — without needing to build them yourself.

For example, an AI agent can chat with a lead, qualify them, and, using the Scheduling API, instantly schedule a meeting — turning conversations into booked meetings for users.

“Our customers now operate with complete confidence that their AI agents will reliably book appointments during phone conversations. This reliability enables them to deploy voice AI at scale, knowing that every successful conversation translates into a completed business outcome.”

Carlos Parga

Product Manager at Thoughtly

Partner spotlight: See how Thoughtly uses the Scheduling API to power AI phone agents that handle the booking process end to end.

Create custom portals and branded scheduling experiences for your users 

You can also use the Scheduling API to build a custom booking flow directly inside your native apps. Or build integrated portals — like a client dashboard, customer portal, or advisor platform — so users can schedule a meeting with your team.

For example, you could add a custom booking flow to your customer portal, so users can book a call with your customer support team without ever leaving your platform. You control the design and front-end experience, so scheduling feels like a seamless part of your platform, not a handoff to another tool.

For example, The University of Sydney has integrated Calendly’s Scheduling API directly into its Student Portal, creating a single, unified platform where students can book academic advising, wellbeing, IT, and facility appointments in one place. 

“This streamlined experience has significantly improved accessibility and efficiency for both students and staff. It provides a consistent booking interface across all services, supports data-driven planning through usage insights, and ensures students can schedule appointments in under two minutes, delivering a more connected and satisfying student experience.”

Ryan Mouthaan

Senior Project Manager at The University of Sydney

API v2

Use API v2 (core REST API) to manage users, Event Types, availability, scheduled events, and much more. V2 includes endpoints for availability and Event Type management so you can seamlessly integrate Calendly into your product. Plus, you can use OAuth 2.0 to connect and retrieve user data.

Let users sign up for Calendly without leaving your app

With OAuth 2.0, users can create a new Calendly account and start scheduling without leaving your product — eliminating drop-offs and enhancing their experience. 

Webhooks

With webhooks, your app receives Calendly data in real time whenever an event is booked, rescheduled, or cancelled. This makes it easier to build integrated apps that trigger follow-up actions automatically, like updating CRM records or sending custom notifications.

For example, you can build an integration that allows your users to automatically log meetings in a CRM when they’re booked, send custom notifications when a meeting is cancelled, or trigger next steps in their marketing automations. 

How ActiveCampaign automates workflows with API v2 and webhooks

ActiveCampaign uses Calendly webhooks and API v2 in their Calendly integration. The integration brings users’ Calendly contacts into ActiveCampaign and adds them to specific lists or segments, so users can send them personalized follow-ups. Users can also automatically move contacts through the sales pipeline based on Calendly activity.

“Using the Calendly APIs and associated documentation, we were able to build and launch an integration quickly — an integration that continues to grow in popularity, bringing additional automation capabilities through Calendly.”

Shay Howe

Chief Strategy Officer at ActiveCampaign

Partner spotlight: Learn more about how and why ActiveCampaign built a Calendly integration for their users.

Note: Calendly users must be on a paid plan to use applications requiring webhooks.

JavaScript embed

Use a JavaScript API call to add your Calendly booking flow to your website, or embed your users’ Calendly booking flows within your apps and integrations. It’s the quickest way to create an embedded native scheduling experience, while still leveraging Calendly’s backend.

Embed Calendly on your website

There are three embed options that can be customized to fit your native look and feel with no coding required: inline, pop-up widget, or pop-up text.

For more control over how Calendly works on your website, you can use an advanced JavaScript embed API call to customize how and when Calendly appears, including:

• Pre-filled invitee information

• Event tracking

• Hiding specific details

Embed scheduling into your product

You can also use embed API calls to display users' booking pages within your app. End users benefit from Calendly's scheduling flow, reminders, and Workflows without ever leaving your environment. For example, popular tools including Typeform, Kajabi, and Pendo use Calendly’s embed functionality to enable users to embed booking pages directly within their forms, pages, or in-app messages.

“Calendly embed API brings the best to the table: quick development with a small amount of code needed and an interface that integrates seamlessly into our product. Now our customers can effectively qualify their leads using Typeform and schedule meetings with them, all in a single interaction.”

Raúl Vallejo

Former Lead Product Manager at Typeform

Customize your team’s Calendly experience

Calendly APIs aren’t only for building integrations — they can also be used to tailor how your own team uses Calendly. Create lightweight customizations that make scheduling fit better into internal workflows. 

For example, you can: 

• Find and share scheduling page links for your team members as an admin

• Track and report on all scheduled events

• Route scheduling data to the right rep or agent based on business requirements

• Auto-generate and send links in response to specific user actions

And more!

“People can fill out a contact form on [our partner’s] website to connect with us. With Calendly’s API, that information comes over to our system and the customer gets immediately routed into the right home loan specialist’s pipeline. It’s been a game-changer.”

Nancy McMahan

Director of Client Engagement at Churchill Mortgage

Customer spotlight: Learn more about how Churchill Mortgage saves time and serves customers with Calendly.

Start building with Calendly APIs

With our growing API platform, it’s easy for developers, product teams, and Calendly users to integrate Calendly’s powerful scheduling capabilities into their own solutions. 

Everything you need to get started with Calendly APIs is in the Developer Portal. There you’ll find reference docs, guides, and sample code to help you start building.

For questions, examples, or feedback, join the Calendly Developer Community to connect with other builders and share ideas.