WhatsApp uses QR codes for two completely different jobs, and mixing them up is the source of most confusion (and one nasty scam). The login QR signs a computer in to YOUR account. The contact QR lets someone else start a chat WITH you in one scan.
This guide explains both, shows how to create and share a QR for your own number, covers the linked-devices system behind the login QR, and closes with the security rules that keep a scanned code from becoming a stolen account.
The two WhatsApp QR codes
Rule of thumb: you scan a login QR yourself, on a screen you opened yourself. You hand a contact QR to others. Any situation where someone else asks YOU to scan a code "to verify" or "to get a discount" deserves suspicion, because scanning the wrong login QR gives away your account.
- Login QR: shown by WhatsApp Web or the desktop app. Scanning it FROM YOUR PHONE links that computer to your account as a companion device. It grants access; treat it like a key.
- Contact QR: generated in your app’s settings. Anyone scanning it gets your number and a ready-to-send chat with you. It shares your identity; treat it like a business card.
Linking a device with the login QR
- 1
Open the target device
Go to web.whatsapp.com in a browser, or open the WhatsApp desktop app. A QR code appears.
- 2
Open Linked Devices on your phone
WhatsApp (or WhatsApp Business), three-dot menu or Settings, Linked Devices, Link a Device.
- 3
Scan the code on the screen
The device loads your chats in seconds and keeps working even when the phone is offline, thanks to multi-device.
- 4
Know the limits
Up to four companion devices per account. A companion unlinks itself after around 14 days without the phone coming online, and logging out of the phone unlinks everything.
Creating your contact QR code
People who scan your contact QR do not need your number saved, and you do not need theirs: the scan opens the chat directly. For a business this is the cleanest bridge from the physical world into a conversation, and every conversation started this way also unlocks clickable links from you and future broadcast delivery once they save you.
- 1
Open your QR
In WhatsApp: Settings, then the QR icon next to your name. In WhatsApp Business: Settings, Business tools, QR code.
- 2
Share or print it
The share button exports the code as an image: put it on the counter, packaging, flyers, a table tent, your website or an email signature.
- 3
Add a pre-filled message (Business)
The Business app lets the QR carry a default message, so scans arrive as "Hi, I saw your offer" instead of an empty chat.
- 4
Reset if it leaks
The QR menu has Reset: the old code stops working everywhere it was printed, and a new one takes its place. Resetting does not affect existing chats.
Related: How to send links on WhatsApp · WhatsApp broadcast messages: the complete guide
Generating a QR from a wa.me link
The contact QR is one option; the other is making the QR yourself from a click-to-chat link. Build https://wa.me/YourNumber?text=YourEncodedMessage, feed it to any QR generator, and you control the pre-filled text per placement: one message for the shop window, another for the invoice footer, a third for the trade-show banner.
Because each placement carries its own pre-filled text, the first message tells you where the customer found you: free attribution with zero tracking scripts.
QR security: the rules that matter
- Never scan a login QR that someone sent you or that appears anywhere other than web.whatsapp.com or the official desktop app you opened yourself. Scanning an attacker’s login QR links YOUR account to THEIR computer.
- Review Settings, Linked Devices whenever in doubt, and log out any session you do not recognize. Each entry shows the platform and last-active time.
- Enable two-step verification so that even a stolen SIM or verification code cannot quietly re-register your number.
- Your contact QR is safe to publish by definition; the worst anyone can do with it is message you. Reset it if you want old prints invalidated.
QR codes as business infrastructure
For a business, the QR is not a gimmick; it is the onboarding funnel. A code at the register, on the van, on the receipt or on the website turns a physical encounter into a WhatsApp conversation with zero typing, and conversations, unlike foot traffic, have history, context and follow-up.
The same linked-devices mechanism behind the login QR is also how modern team tools connect. Spun, for example, links to your existing business number with one QR scan, exactly like WhatsApp Web, and then gives the whole team their own logins to a shared inbox: assignment, labels, full history, AI drafting and summaries, transcribed voice notes and scheduled follow-ups, with no Business API application and no per-message fees.