How to Build an Event Registration Site: RSVPs, Tickets and Check-In
How to build an event registration site: RSVP forms, capacity and waitlists, paid tickets, confirmation emails with calendar invites, and check-in on the day.
Mythex Team · · 7 min read
An event registration site needs an event page with the date, time and place, a registration form that respects capacity, a confirmation email with a calendar invite, an attendee list for you, and a quick way to check people in on the day. Paid events add ticket types and a checkout through a payment provider. You can build all of this with an AI app builder by describing the event and the registration rules; the parts that deserve the most testing are capacity limits and what happens when someone cancels.
What the site needs
For attendees
- Event page: name, date, start and end time with the time zone, venue with a map link (or "online" with a note on when the link arrives), agenda, speakers or hosts, price, and who it's for
- Registration form: name, email, and only the questions you'll actually use (dietary needs, company, T-shirt size)
- Confirmation screen and email with the details, a calendar file (.ics) to add it to their calendar, and a way to cancel
- Reminder email a day or two before, with directions or the online link
For organisers
- Attendee list with search, filters by ticket type, and CSV export
- Capacity and waitlist rules
- Check-in view that works on a phone at the door
- Messages to attendees (a change of room, a delay)
- Admin for events if you run more than one
The data behind it
| Data | Main fields |
|---|---|
| Event | Title, description, start, end, time zone, venue or online link, capacity, status (draft, open, closed) |
| Ticket type | Event, name (e.g. Standard, Student), price, quantity available, sale start and end |
| Registration | Event, ticket type, name, email, answers to custom questions, status (confirmed, waitlisted, cancelled), payment reference, created at |
| Check-in | Registration, checked in at, checked in by |
Decisions to make before you build
Free RSVP or paid tickets
Free events are much simpler: no checkout, no refunds, no tax. The catch is no-shows. Free events often see a large share of registrants not turn up, so many organisers let registrations go somewhat past room capacity, or send a "still coming?" email that lets people release their spot.
Paid tickets need a payment provider such as Stripe, a webhook that confirms the registration only after payment succeeds, a refund policy, and possibly sales tax on tickets depending on where you are. See how to add payments to your app.
One event or many
A single conference or launch party can be one page with a form. If you run a monthly meetup, workshops or classes, build it as an events list with a shared registration system from the start. Adding "events" as a concept later means restructuring the data.
Waitlist behaviour
When an event is full, you can close registration, or take waitlist sign-ups. If someone cancels, you can either email the next person on the waitlist and give them a time limit to accept, or move them in automatically. Automatic is easier to run; the time-limited offer works better for paid tickets, where the next person has to pay.
Online, in person or hybrid
Online events need the joining link delivered at the right time (in the confirmation, or only in the reminder so it's less likely to be shared). In-person events need the venue, access notes and a check-in plan. Hybrid events need two ticket types with different information in each email.
Build it step by step
Step 1: Write the event details
Collect the real title, dates, time zone, venue, agenda, capacity and ticket types. Decide your cancellation and refund policy and write it in one or two sentences.
Step 2: Write the first prompt
Describe the event, the form, the rules and the organiser's view:
Build a registration site for Bristol Product Night, a free monthly meetup for product managers. Show upcoming events with date, time (UK time), venue with a map link, agenda and spots left. Each event has a capacity; the form asks for name, email, company and role. When an event is full, new sign-ups join a waitlist, and if someone cancels, the first person on the waitlist is moved in. Save everything to a database. Confirmation screen with an "Add to calendar" file and a cancel link. Private admin page: create events, see registrations with search and CSV export, and a phone-friendly check-in list with a big "Checked in" button. Friendly, modern design.
Step 3: Test capacity with more than one person
Capacity bugs only show up when two people register at nearly the same moment. Set a test event's capacity to 2, then register from two browsers quickly, then a third time. You should end with two confirmed and one waitlisted, never three confirmed. Ask for the capacity check to happen on the server inside the same database operation that saves the registration.
Also test: cancelling a confirmed spot moves the right person off the waitlist; the confirmation shows the correct time in the right time zone; the calendar file opens correctly on a phone.
Step 4: Add emails
Confirmation, reminder, and "you're off the waitlist" emails need an email provider and a verified sending domain. Keep each one short and make the date, time and place the first thing people read. How to send emails from your app covers the setup.
Step 5: Add paid tickets if you need them
Add ticket types with their own quantities, a checkout through your payment provider, and a registration status that only becomes "confirmed" when payment succeeds. Decide what happens to an unfinished checkout: hold the ticket for a few minutes, then release it.
Step 6: Prepare for the door
On the day, the venue's wifi may be poor and the queue will be long. Make the check-in list fast to search by name, big enough to tap on a phone, and export a printed backup list the night before. For larger events, a QR code in each confirmation email that staff scan speeds things up, and should mark the ticket as used so it can't be scanned twice.
Common mistakes
- Missing time zone. Especially for online events, "7pm" means different things to different attendees. Always show the time zone.
- Checking capacity only when the page loads. Two people can both see "1 spot left".
- Asking too many questions. Every extra field loses registrations. Ask for anything non-essential after they sign up.
- No cancel link. People who can't come won't free up their spot, and your waitlist never moves.
- No reminder. Reminders tend to reduce no-shows; don't skip them.
- Sending the online link to the whole world. Put it in emails to registered attendees, not on the public page.
- Editing the event date without telling anyone. Changes need an email to everyone registered.
What it costs
For a free event, your costs are small: hosting, a database, an email provider for confirmations and reminders, and a domain if you want one. Paid events add payment processing fees per ticket. Ticketing platforms typically charge per-ticket fees, sometimes passed to the buyer; compare their current pricing against the time you'll spend building and running your own.
When a ready-made product is the better choice
Ticketing and RSVP platforms such as Eventbrite, Luma, Meetup and Tito each offer their own mix of payments, refunds, reminders, check-in tools and waitlists, already built and tested. Some also help people discover events. Use one when:
- It's a one-off event and you need it live today
- You want the platform's audience to help sell tickets
- You need a mature check-in app for thousands of attendees
- You don't want to deal with refunds and payment disputes
Build your own when you run recurring events and want the attendee list in your own database, when you need custom registration logic (approval before confirming, member-only pricing, application-based events), or when you want the page to look and feel like your brand. The event page itself follows the same rules as any page that asks for a sign-up; see how to build a landing page that converts. If your "event" is really one-to-one appointments, how to build a booking app is the better guide.
Building it with Mythex
Mythex is an AI app builder: you describe the event and the rules, and it builds the event pages, registration form and admin views in a live preview, adding a database to the project to store registrations. You can type /test to have it click through registration in the preview and report what breaks, which is useful for the capacity and waitlist flows. Publishing is available on Free and Pro, with custom domains on Pro. Mythex doesn't include ticketing, email or payments as built-in products: you connect your own Stripe account for paid tickets and your own email provider for confirmations, with keys stored in project secrets. See the docs on Stripe payments, sending email and App Testing.
The event registration page template is a good first prompt to start from, or browse more website templates.
Questions
What does an event registration site need?
An event page with date, time, time zone and location, a registration form, a confirmation email, an attendee list for the organiser, and a way to check people in. Paid events also need ticket types and a checkout.
How do I stop an event from overselling?
Check the remaining capacity on the server at the moment each registration or payment is confirmed, not only when the form loads. When the event is full, close registration or move new sign-ups to a waitlist automatically.
How do I check people in at an event?
The simplest method is a searchable attendee list on a phone or tablet with a check-in button. For larger events, each confirmation email can include a QR code that staff scan to mark the ticket as used.
Should I use Eventbrite or build my own registration site?
Ticketing platforms are faster to set up, handle payments and refunds, and can help people discover your event, in exchange for fees and their branding. Your own site makes more sense for recurring events, custom registration questions, or when you want the attendee data and branding fully in your hands.