QR codes for audience Q&A: a 5-point checklist

A QR code is the highest-leverage pixel on your slide. Done right, it turns passive viewers into active participants in three seconds. Done wrong, the room stares at a blurry pixel block and gives up.

1. Size: at least 240 × 240 pixels on-screen

At 1080p, a QR code needs to be at least 240 pixels square for a phone camera to read it from ~3 meters away. Bigger is fine. Smaller rarely works in practice.

2. Contrast: dark on light, always

QR codes work by contrast. Pure dark modules on a pure light background scan reliably. Colored codes scan sometimes. Codes on gradients or over photos scan rarely. Don't be cute.

3. Placement: top-right of the current slide

The top-right corner is the best place because:

• It doesn't overlap with your slide's content on most layouts
• People scanning in the back of the room look up, not down
• It's visible even after attendees have scrolled on their phone to

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A pinned QR in a sidebar (the way TA pilot does it) is even better because it stays on the same pixel every slide.

4. Accompany with a short code

The QR code alone isn't enough. Some phones refuse to scan. Some attendees are too far. Always include a short code (like of4f4fb5) and a URL (tapilot.com/s/of4f4fb5) nearby so people have a fallback.

5. Verify scanability before the talk

Open your camera app. Stand where the back row would stand. Point at the screen. If it scans within two seconds, you're fine. If it doesn't, make the QR bigger, increase the contrast, or change the slide's background.

The TA pilot sidebar renders the session QR at the right size and keeps it on-screen the entire talk — so you only have to verify it once.