QR code use cases

QR codes work when they remove a step someone was going to resent. Here are the places that genuinely holds, and the format and size to use for each.

The pattern that separates a code people scan from one they ignore is simple: it has to be faster than the alternative, and it has to say what it does. A code with no label is a coin flip. “Scan for the menu” is a reason.

Restaurant and café menus

Hospitality

A code on the table opens the menu without an app or a printed card per cover. It also lets you change prices without a reprint — as long as it points at a web page you control, rather than a PDF you would have to re-upload.

Size
3–4 cm on a table tent, dark-on-light

Guest Wi-Fi

Cafés, hotels, holiday lets, offices

The single most appreciated QR code there is. Guests join by pointing a camera instead of squinting at a password taped to a router. Use a guest network rather than your main one, because anyone who photographs the card keeps access indefinitely.

Size
3 cm on a card, laminated if handled

Business cards and email signatures

Anyone who networks

A vCard code saves your details straight to the phone, so nobody re-types a name and gets it wrong. Keep the fields lean — every extra one makes the pattern denser, and a business card does not have room for a dense code.

Size
2 cm minimum; test before a print run

Event posters and tickets

Promoters, venues, conferences

A calendar code puts your event straight into someone’s phone while they are standing in front of the poster — the moment intent is highest. Print the date in plain text too, because not everyone scans.

Size
One tenth of the reading distance — 30 cm on a wall poster

Estate agent boards and window cards

Property

Someone standing outside a house at 9pm is your warmest possible lead. A code on the board takes them to the listing, a video tour, or straight to a WhatsApp chat with the agent.

Size
10–15 cm on a board read from 1–2 m

Product packaging and labels

Retail, food, manufacturing

Instructions, allergen details, care guides, and warranty registration all fit behind a code instead of a folded leaflet. Point it at a page you control so you can correct mistakes after the print run.

Format
URL code
Size
1.5–2 cm; increase error correction if the surface curves

Shop signage and customer support

Retail, services

A code that opens a pre-written message removes the hardest step — working out what to say. An SMS or email code with the subject pre-set to a branch or table number routes the enquiry for you.

Size
5–8 cm at counter height

Venue entrances and meeting points

Festivals, sites, large campuses

Street addresses fail for festival gates, trailheads, and the back entrance of an industrial estate. Coordinates drop people on the exact pin, which is the difference between arriving and phoning you.

Size
15 cm+ outdoors, laminated

Museums, galleries and trails

Culture and education

A code beside an exhibit links to audio, a translation, or a deeper explanation, without cluttering the label. It is also the cheapest multilingual option there is — one code, a page that detects language.

Format
URL code
Size
4–5 cm at arm’s length

Donations and tips

Charities, buskers, small traders

A payment or crypto code removes the "I have no cash" objection entirely. Verify the address by scanning your own code before it goes anywhere public — a wrong address is unrecoverable and unreadable to humans.

Size
5 cm+, high contrast

Three things that decide whether it gets scanned

  1. Say what happens. “Scan to join our Wi-Fi” converts far better than a bare code, because scanning an unlabelled code is a small act of trust most people will not extend.
  2. Size it for the distance. The working rule is 10:1 — the code should be about one tenth as wide as the distance it is read from. A poster read from three metres needs roughly 30 cm.
  3. Test on a real phone, in the real place. Lighting, glare on laminate, and the curve of a bottle all defeat codes that scan perfectly on a monitor.

Where QR codes do not help

They are a poor fit when the alternative is already easy. A code on a website you are already viewing, or one that points at a homepage the visitor could have typed, adds a step rather than removing one. They also fail wherever people cannot comfortably hold up a phone — while driving, on a busy escalator, or anywhere the code is behind glass at an awkward angle.

One more caution worth knowing: because a QR code is unreadable to humans, stickers placed over legitimate codes on parking meters and payment terminals are a real and growing scam. If you deploy codes in public, check them periodically, and prefer printing directly onto the surface over applying a sticker.

Pick a format on the QR types page, or read the guide for error correction, sizing and the reasons codes fail to scan.