Real-Time Calendly Availability API Endpoint Generator - n8n Workflow

Developers building custom booking interfaces or scheduling widgets.
Product Managers needing aggregated, real-time availability data.
Users seeking robust n8n templates for integrating scheduling APIs.
Anyone needing to expose Calendly data securely via a custom n8n API endpoint.

This sophisticated n8n workflow transforms the complex Calendly API into a simple, robust availability checking endpoint. Instead of manually polling multiple Calendly resources, this single n8n trigger allows external applications (like your website, CRM, or chatbot) to query real-time availability for specified events over a defined period (defaulting to 7 days). The workflow handles authentication, user discovery, event type selection, and complex data formatting, making this n8n node sequence extremely valuable for high-performance scheduling integrations. This is a must-have n8n template for service providers who rely on Calendly for booking.

This automation begins with the Webhook Trigger n8n node, set to listen for a POST request at the path /check-calendly-availability. This n8n trigger allows the external application to pass optional parameters, specifically eventtypeuri (to target a specific event) and days_ahead (defaulting to 7).

1. Configuration and User Retrieval: The data is first captured by the Set Configuration n8n node. It then uses the first HTTP Request n8n node to authenticate and fetch the current Calendly user's details (/users/me). The Extract User Info node parses essential URIs needed for subsequent API calls.


2. Event Type Identification: The workflow proceeds to the second HTTP Request n8n node, Get Event Types, fetching all active event types associated with the user. The Select Event Type n8n node applies logic: if a specific event type was requested via the initial n8n trigger, it uses that; otherwise, it defaults to the first active event type found.


3. Availability Check: The Get Available Times n8n node performs the crucial check, querying the Calendly API for available slots between tomorrow and the configured number of days ahead. This complex n8n workflow handles the ISO date formatting dynamically.


4. Formatting and Response: Finally, the Format Availability n8n node organizes the raw slot data, calculating totals, identifying the next available slot, and grouping slots by day for readability. The final Respond with Availability n8n node returns a clean, comprehensive JSON response, completing the cycle initiated by the n8n trigger.

To deploy this powerful n8n workflow and start using this n8n template, follow these steps:

1. Import the Workflow: Copy the provided JSON code and paste it directly into your n8n instance via the 'New' menu (Import from JSON).


2. Calendly Credentials: This n8n workflow relies on the Calendly OAuth2 API credential type. You must first set up a Personal Access Token or OAuth2 App within your Calendly account. In your n8n instance, create a new Credential of type 'Calendly OAuth2 API'.


3. Apply Credentials: Go to the Get Current User, Get Event Types, and Get Available Times n8n node instances. Ensure the correct Calendly credential is selected for the 'Authentication' setting.


4. Activate and Test: Activate the n8n workflow. The Webhook Trigger will generate a unique URL (e.g., YOURN8NURL/webhook/availability-checker). Test the endpoint by sending a POST request to this URL, optionally including {"days_ahead": 3} in the body.

Webhook Trigger (availability-checker): The initial n8n trigger, configured for a POST request to /check-calendly-availability. It sets the process in motion and captures optional request body parameters.
HTTP Request (Get Current User, Get Event Types, Get Available Times): These three key n8n node operations handle all communication with the Calendly API, performing authenticated GET requests to fetch user data, list event types, and retrieve real-time availability slots respectively. They use dynamic expressions for query parameters (e.g., user URI, date range).
Set (Set Configuration, Extract User Info, Select Event Type, Format Availability): These versatile n8n node elements are critical for data manipulation. They extract specific fields (like user URIs and selected event URIs), calculate future dates, format raw ISO time strings into human-readable formats, and restructure the final availability data into a clean, hierarchical JSON object.
Respond with Availability: The final n8n node, which formats the rich context gathered throughout the n8n workflow into a structured JSON response, including user details, event type details, and categorized lists of available slots.