QR codes in presentations
The QR code on the last slide is the most common call to action at conferences and in classrooms, and the most commonly too small. A code that looks fine on your laptop can be unscannable from row 20.
Size the code for the back of the room, leave it up long enough, and point it at something worth scanning: the slides, the resources or a two-question feedback form.
What to link from QR codes on presentations
Get the slides
A code that opens your slides or resources, so the audience stops photographing every slide.
Session feedback
A two-question form on the last slide while the audience is still seated.
Connect with the speaker
A vCard Plus or LinkedIn code for networking after the talk.
Live polls and Q&A
A code that opens your polling or Q&A tool for the session.
Which QR code to use
Static codes are free and need no account, but can't be changed after printing. Dynamic codes and hosted pages can be edited at any time, count every scan, and keep working on every plan, even if you cancel.
Feedback and forms page
Star ratings, NPS and questions, with responses collected in your dashboard.
A short session feedback form with star ratings and a comment.
Build it in the dashboardvCard Plus page
A digital business card with photo, contact buttons and a Save contact button.
Your contact card with photo and socials, for networking after the talk.
Build it in the dashboardPDF page
An uploaded PDF people can read in the browser or download.
The slide deck as a PDF, replaceable with the corrected version after the talk.
Build it in the dashboardHow big to print it
| Where people scan | Distance | Minimum code width |
|---|---|---|
| Meeting room screen | 4 m (13 ft) | 46.4 cm (18.3 in) |
| Lecture hall, middle rows | 10 m (33 ft) | 1.16 m (3.8 ft) |
| Conference hall, back rows | 20 m (66 ft) | 2.32 m (7.6 ft) |
For a dynamic short link such as https://qrdx.dev/q/aB3dE5f at error correction Q, without the blank margin. Static Wi-Fi, vCard or long URL codes hold more data and need to be larger. Check yours with the print size calculator and the scan checker.
Placement tips
- Make the code fill much of the slide height: from 10 m it needs to be over a metre wide on screen.
- Leave it up for at least 30 seconds, and put it on the first and the last slide.
- Keep a white quiet zone around the code; dark slide templates need a white box behind it.
- Use a short link so the code has fewer, larger modules on projectors with low resolution.
Call-to-action copy
A code with a reason to scan beside it gets more scans than a bare code. Lines to print next to yours:
- Scan for the slides and resources
- Rate this talk in 20 seconds
- Let's connect
- Ask a question
QR codes on presentations: FAQ
How big should a QR code be on a slide?
Big enough for the back row: about a tenth of the distance, a bit more for a short link. From 10 m, over a metre on screen; in a small room, 40 to 50 cm.
How long should I show a QR code in a presentation?
At least 30 seconds, and repeat it at the end. People need time to unlock their phone and open the camera.
Can I update the link after the talk?
Yes, with a dynamic code. Point it at the recording once it's online; people who scanned during the talk can come back later.