ottercraft.dev

Guide · OtterQR

Make a Wi-Fi QR code for guests

Nobody wants to read out a twenty character password, and nobody wants to type it. A square on the fridge, or on a card by the bed, does the job in one scan.

Open OtterQR →

Make it

  1. Open qr.ottercraft.dev and press Wi-Fi.
  2. Type the network name exactly as it appears when you look for it on a phone. Capitals count, and so do spaces.
  3. Type the password. Leave the security on WPA unless you know the network is older, or open.
  4. Tick Hidden network only if the network does not broadcast its name.
  5. Download the PNG for a screen, or the SVG if you are printing a card.

Scanning it

Point the camera app at it. iPhones and Android phones both recognise a Wi-Fi code and offer to join, with no app in between. A phone that has never seen the network still needs to be in range, and some corporate phones block the shortcut through their device policy.

What is actually in the code

A Wi-Fi code is a short piece of text in a shape phones agreed on years ago. It looks roughly like this:

WIFI:T:WPA;S:Otter Lodge;P:the-password;;

Which means the password sits in the code in plain text. Anyone who can photograph the square can read it, the same way anyone who can read the sticker on the back of the router can read that. This is not a flaw in the code, it is what makes it convenient, and it is the reason the next section matters.

Put it on the guest network

Almost every router made in the last decade can run a second network for visitors, usually called something like Guest Wi-Fi. Devices on it reach the internet and nothing else, so a scanned code cannot lead anyone to your laptop, your NAS or your printer. Turn that on, give it its own password, and make the code for that.

If you print the code and stick it somewhere public, treat it as published. Change the guest password when you want the old cards to stop working, and print new ones.

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