Minimum on-screen duration for a QR code

The time budget

Walk through what a viewer physically does between seeing a code and landing on the page. The steps are fixed; only practice changes their speed:

Step	Primed viewer	Unprimed viewer
Notice the code, decide to scan	— (already decided)	3–6 s
Pick up and unlock the phone	2–3 s	2–3 s
Open the camera	1–2 s	1–2 s
Aim and frame the code	2–3 s	2–3 s
Focus and expose	1–2 s	1–2 s
Decode	< 0.5 s	< 0.5 s
Read the prompt and tap	1–2 s	1–2 s
Total	≈ 8–12 s	≈ 12–19 s

The decode itself is nearly free — good codes decode in a camera frame or two. Everything expensive is human. A "primed" viewer knew the code was coming and has the phone in hand; most viewers are not primed.

The recommendation

Hold the code on screen for at least 15–20 seconds, and treat that as a floor, not a target. If the format allows it, the better answer is no timer at all: a persistent code in a corner for the whole segment converts everyone who decides to scan at any point, instead of only those who react inside your window.

Context	Guidance
TV advert	≥ 15–20 s, or corner placement for the full spot — see QR codes in TV ads
Presentation slide	leave the code up through the whole section, and again on the closing slide — see slide decks
Livestream	persistent overlay beats a flashed graphic
Digital signage loop	code visible ≥ 15 s per loop and recurring every loop — see digital signage

Duration cannot fix size

The two budgets are independent: a code held for a minute still fails if it breaks the 10:1 distance rule. Check size against the size-by-distance table and the frame-fraction arithmetic in QR codes on video first — then worry about seconds.

Priming buys back seconds

Announcing the code before it appears — a presenter saying "there's a code coming up on the next slide", a lower-third saying "scan in 5 seconds" — moves viewers from the unprimed to the primed column and saves 4–7 seconds of the budget. Conversely, visible countdowns on the code itself add pressure and fumbling; if people can miss it, pair the code with a readable short URL so a missed scan is not a dead end.

FAQ

How long should a QR code stay on screen?

At least 15–20 seconds. A viewer needs roughly 8–12 seconds to unlock, aim, focus and decode when already intending to scan, and several seconds more to notice and decide. A persistent corner placement is better than any timed window.

How long does a QR code need in a TV ad?

Fifteen to twenty seconds minimum, which in practice means most of a 30-second spot. Many campaigns instead keep a smaller code on screen for the full duration — every second it is absent is a viewer who cannot convert.

Is 5 seconds enough for a QR code?

No. Five seconds barely covers unlocking a phone and opening the camera. Even a fully primed viewer needs about 8–12 seconds; viewers who first have to notice the code need 15 or more.

Does animating the QR code help people scan it in time?

Animation can attract attention to the code's location, but the code itself must stay still and continuously decodable while people aim. Position or scale animation during the scanning window resets the viewer's aim and wastes the seconds you paid for.