How to Create an Appointment Booking System with Login Using Google Apps Script | C37

A booking form that cannot double-book. The visitor picks a date, sees that day's slots laid out in green and red, and can only take one that is genuinely free — and the moment they take it, it turns red for everyone else.

The order of the form is the feature

Name, phone and email stay locked until a slot is selected. That is deliberate: people want to know whether the time they need is even available before they hand over their details, and asking for the details first is how booking forms get abandoned. Choose the slot, the fields unlock, add a note if there is one, and book.

Both sides get the email

A confirmed booking emails the customer their confirmation and emails the admin that a booking has come in, so nobody has to sit refreshing a spreadsheet to find out.

Admin panel

Sign in and every appointment is in one table with counts across the top — total, completed, cancelled and pending. A walk-in in front of you can be added on the spot, and the slot dropdown offers only the times still free on the date you chose, so the manual entry cannot collide with an online booking either. Statuses are set from the same screen.

Getting the list out

Copy the table, download it as CSV or PDF, or narrow it with a date range filter that refuses a start date after the end date rather than silently returning nothing. Clear the filter and the full list comes back.