Schedule appointments from a booking form with Google Calendar and Gmail

How it works This workflow creates a complete appointment booking system — no external scheduling tools needed. It serves a styled HTML booking form via webhook, checks your Google Calendar for availability, and lets visitors pick an open 30-minute slot. On submission, it creates a calendar event, sends a confirmation email via Gmail, and shows a success page. - A GET webhook serves the booking page, which reads your Google Calendar to show only open time slots for the next 30 days - Visitors pick a date/time, fill in their name, email, and an optional message, then submit - A POST webhook receives the form, calculates the end time, creates a Google Calendar event, and sends a styled HTML confirmation email with an "Add to Calendar" link - The visitor sees a branded success page confirming their booking Set up steps 1. Google Calendar OAuth2 — Connect your Google account with Calendar read/write access. Takes 5 minutes if you already have OAuth credentials in Google Cloud Console. 2. Gmail OAuth2 — Connect your Gmail account for sending confirmation emails. Can reuse the same Google OAuth app. 3. Configure your availability — In the "Calculate Available Slots" node, adjust workingDays (default: Mon–Fri), startHour/endHour (default: 9 AM–2 PM), slotDuration (default: 30 min), and the timezone offset (default: +02:00 for EET). 4. Activate the workflow — The booking form will be live at your n8n instance's webhook URL: your-n8n-url/webhook/booking 5. Optional: Customize branding — Edit the HTML/CSS in the "Build HTML Form" and "Show Success Message" nodes to match your brand colors and copy.