When a booking is successfully created in Cal.com, users can be redirected to a custom success page by enabling ‘Redirect to a custom URL after a successful booking’ option in the Event Type’s Advanced settings page. This guide documents all the query parameters that are forwarded to your custom success URL when ‘Forward parameters’ option is enabled (which is the default).

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Overview

Cal.com automatically appends booking information as query parameters to your custom success redirect URL. These parameters allow you to display booking details, or integrate with your own systems. Example redirect URL: 
https://yoursite.com/booking-success?uid=abc123&title=30min%20Meeting&startTime=2024-01-15T14%3A00%3A00.000Z&attendeeName=John%20Doe&email=john%40example.com

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Quick Reference

ParameterAlways IncludedDescription
uid✅Unique booking identifier
title✅Event type title
startTime✅Start time in UTC
endTime✅End time in UTC
email✅Primary attendee email
isEmbed✅Boolean flag indicating embed booking
description⚠️Event description (when available)
location⚠️Meeting location (when set)
hostName⚠️Host name(s) (when available)
hostStartTime⚠️Start time in host timezone (when available)
attendeeName⚠️Attendee name (when available)
attendeeStartTime⚠️Start time in attendee timezone (when available)
attendeeFirstName⚠️First name from booking form (when provided)
attendeeLastName⚠️Last name from booking form (when provided)
guestEmails⚠️Guest emails (when guests added)
phone⚠️Phone number (when provided)

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Core Booking Parameters

uid - Unique identifier for the booking
  • Always included
  • Example: 9ybDCbazSYpJHthpxG5EDM
  • Usage: Use this to fetch additional booking details via API or store in your database
title - The event type title
  • Always included
  • Example: 30 Minute Meeting
description - Event type description
  • Included when event has description
  • Example: Quick sync meeting to discuss project updates
startTime - ISO 8601 formatted start time in UTC
  • Always included
  • Example: 2024-01-15T14:00:00.000Z
endTime - ISO 8601 formatted end time in UTC
  • Always included
  • Example: 2024-01-15T14:30:00.000Z
location - Meeting location or video conference URL
  • Included when location is set
  • Example: integrations:daily (Cal Video), integrations:zoom (Zoom). More possible values here

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Host/Organizer Parameters

hostName - Host name(s), comma-separated for multiple hosts
  • Included when host information available
  • Example: Jane Smith,Mike Johnson
hostStartTime - Start time formatted in host’s timezone
  • Included when host timezone available
  • Example: 2024-01-15T09:00:00-05:00

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Attendee Parameters

attendeeName - Name of the person who booked
  • Included when primary attendee name available
  • Example: John Doe
attendeeStartTime - Start time in attendee’s timezone
  • Included when attendee timezone available
  • Example: 2024-01-15T06:00:00-08:00
attendeeFirstName - First name from booking form
  • Included when first name provided in booking form
  • Example: John
attendeeLastName - Last name from booking form
  • Included when last name provided in booking form
  • Example: Doe
guestEmails - Comma-separated list of guest emails

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Booking Context Parameters

email - Primary attendee’s email address phone - Phone number from booking form
  • Included when phone number provided
  • Example: +1234567890

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System Context Parameters

isEmbed - Boolean flag indicating if booking was made via embed
  • Always included
  • Example: false

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Troubleshooting

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Common Issues

Missing Parameters
  • Some parameters are only included when data is available
URL Encoding Issues
  • Always use decodeURIComponent() in JavaScript or equivalent in other languages
  • Special characters like @, +, spaces are URL encoded
Date/Time Handling
  • startTime and endTime are always in UTC (ISO 8601 format)
  • hostStartTime and attendeeStartTime include timezone information
  • Convert to local time as needed for display

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Security Considerations

  • Always validate and sanitize parameters before using in database queries
  • Don’t trust parameter values - validate against your expected data types