Can I create a unique identifier (ie QR code) for event registrations?

We are creating an event registration page and would like to generate some sort of unique identifier that would be tied to that individual, like a QR code, so we can quickly check people in and later see who attended. Thanks!

Yes, this will be possible to achieve, you may use any of the following widgets to generate the identifier you need: 

1. Unique ID widget: https://widgets.jotform.com/app/autoincrement 

2. Random Value Generator widget: https://widgets.jotform.com/app/random_value_generator 

Then you will need to use the Dynamic QR Code widget since it will generate the code based on the value in a field, you need to use the field's label to link the field with the QR code generator, the widget can be found here: https://widgets.jotform.com/app/dynamic_qr_code 

This guide will help you adding the widgets to your form: https://www.jotform.com/help/252-How-to-Add-a-Widget-to-Your-Form 

I hope this helps.