QR code and control at the entrance: how it works

As you enter, an agent scans your ticket, a small buzzer sounds, and you are inside. But what really happens in those two seconds? Understanding the role of the QR code helps you approach control with a light mind. We'll simply explain how this code works, why it only scans once, and the few gestures that make your passage quick and smooth.

Updated on 2026-06-11 · 3 min read

What exactly is the QR code?

The QR code (or barcode) printed on your ticket is a kind of unique “T0” key. It contains a reference that corresponds to your place in the organizer's system. When the agent scans it, his reader reads this reference and verifies in an instant that the ticket is 'T2' valid and has not already been used 'T3'. You don't have to explain or enter anything: everything happens in the code itself.

What happens during the scan

  1. 1

    You present your ticket

    On the screen of your phone or on paper, you show the QR code to the agent or at the control terminal.

  2. 2

    The reader reads the code

    A camera or scanner captures the code in a fraction of a second. It doesn't need your connection: it's the control system that works.

  3. 3

    The system checks the validity

    The ticket is compared to the list of seats sold. If it is valid and still unused, it is accepted.

  4. 4

    The ticket is marked “used”

    A green signal or beep confirms entry. The code then goes to “already scanned” status to prevent it from being used a second time.

Present your code well for a quick scan

  1. Prepare the 'T0' ticket before arriving in front of the 'T1' agent, so as not to search in the queue.
  2. On mobile, 'T0' increase the brightness 'T1' and turn off dark mode if the code appears grayed out.
  3. Display the QR code in full , without cutting it or reducing it excessively.
  4. On paper, present a clean and uncreased sheet of , with the code flat.
  5. Hold the code 'T0' immobile 'T1' for a few moments in front of the reader, for the duration of the beep.

What if the scan doesn't pass?

Don't panic, it happens and is almost always resolved on site. Most often, it is a display problem: screen too dark, code partially hidden, sheet folded over the code, or insufficient brightness. Adjust the screen, redisplay the entire QR code, and present it again. If the ticket really seems refused, keep calm and your 'T0' order number 'T1' within reach: the reception staff are there to check and direct you.

Frequently asked questions

Do you need an Internet connection to have your ticket scanned?
Not on your side, in principle: it is the control system which reads and verifies the code. However, you need to display the QR code on your screen. To have peace of mind even without a network in line, save the ticket in advance (PDF on the phone or add to Wallet) rather than opening it only from an online link.
Why is my QR code not accepted?
Most often, it is a display problem: screen too dark, code cut or reduced, sheet crumpled on the code. Turn up the brightness, display the code in full, and represent it. If the refusal persists, keep your order number handy and contact the reception staff, who can verify the situation.
Can I send a photo of my ticket to a friend to enter with?
It is risky and not recommended. A QR code can only be scanned once: if the person uses it before you, your own ticket will be refused at entry. To share a seat properly, instead use an official transfer function when it exists, as explained in our guide on transferring an e-ticket.
Does the controller see my personal information when scanning?
The scan mainly checks the validity of the place and its status (used or not). The information displayed depends on the organizer's system; for a nominative ticket, the name can be checked at the entrance. If you have any questions on this point, refer to the conditions indicated on the event page.