Offline Wi-Fi QR Code Generator

Your Device Probably Already Does This

This is the section most Wi-Fi QR articles are missing, and it is the reason they read as though written in 2019. Four operating systems will do this for you, from a network they have already saved, with no third-party anything involved.

• Android

  Settings, then Network and internet, then Internet, then tap the network and choose Share. You confirm your identity, and it draws the code.

  Enough for

  Handing the network to somebody standing next to you, right now.

  Where it stops

  It is a screen, not a file. There is no export, no size control and no vector, and the path has moved between Android versions and manufacturers, so the menu you read about may not be the menu you have.

  Source: Google, Connect to Wi-Fi networks on your Android device

• iPhone and iPad

  Open the Passwords app, choose Wi-Fi, pick the saved network, then tap Show Network QR Code.

  Enough for

  The same job as Android, plus it works for any network the phone has saved rather than only the one it is on.

  Where it stops

  Screen only, and it needs the network to be in your saved list. Apple's separate proximity sharing is a different thing entirely: it needs both devices present and in each other's contacts, so it cannot produce anything you can print.

  Source: Apple, Find and share your Wi-Fi password on iPhone

• Mac

  The same route as iOS: Passwords, then Wi-Fi, then the network, then Show Network QR Code.

  Enough for

  Sharing the office network with somebody at your desk.

  Where it stops

  Screen only. A screenshot of it is a raster image at whatever your display gives you, which is the wrong starting point for print.

  Source: Apple, Find and share your Wi-Fi password on Mac

• Windows

  Settings, Network and internet, Wi-Fi, then Manage known networks. Pick the network, reveal the password, and Windows shows a QR code alongside it.

  Enough for

  Getting a phone onto the network a laptop is already using, without reading a passphrase aloud.

  Where it stops

  Screen only, and it depends on your Windows version. Windows will also draw a code for a mobile hotspot you are running, which is genuinely useful and has nothing to do with your router.

  Source: Microsoft, Connect to a Wi-Fi network in Windows and Microsoft, Use your Windows device as a mobile hotspot

• Linux

  No desktop-wide feature, and none needed. qrencode takes the payload on the command line and writes a PNG or an SVG.

  qrencode -l H -o guest-wifi.svg -t SVG 'WIFI:T:WPA;S:Cafe-Guest;P:flat-white-2026;;'

  Enough for

  Everything, including the printed sign, and it is the only native route on this list that produces a vector.

  Where it stops

  You assemble the payload yourself, which means you own the escaping. Get a character wrong and you get a valid code that will not connect.

So the decision is simpler than the search results suggest. Sharing with a person in the room: use what you have. Putting a code on a card, a window or a room folder: the Wi-Fi generator here exports a vector and handles the characters that break hand-built payloads.

Why Wi-Fi Is the One Payload That Finishes Offline

Wi-Fi is the only common payload that completes its entire job with no connection anywhere in the chain, and that is not a nice coincidence. It has to be true, because the person scanning your sign has no internet yet. That is why they are scanning.

The credentials sit inside the pattern. The phone reads them from the image, hands them to the operating system, and the operating system talks to the access point over radio. Nothing in that sequence needs a server, which is also why the code keeps working if the generator you used disappears.

One distinction to keep straight, because it causes most of the false alarms: joining a network and that network having a working uplink are separate events. A Wi-Fi code that connects a phone to a router with a dead line has succeeded completely. For the wider picture of which payloads finish offline and which only decode offline, the offline generator guide has the measured table.

What Each Network Setting Actually Encodes

Four network configurations, the exact string each one produces, and the string our decoder recovered from the finished symbol. The last column is the point: you can do this to your own code before you print it, and it is the only way to be certain the thing on the card says what you meant.

WIFI:T:WPA;S:Cafe-Guest;P:flat-white-2026;;

WIFI:T:WPA;S:Cafe-Guest-6E;P:flat-white-2026;;

WIFI:T:nopass;S:Airport-Free;;

WIFI:T:WPA;S:Back-Office;P:flat-white-2026;H:true;;

Two things worth noticing. WPA3 does not get its own authentication value, because the field describes the credential type rather than the protocol generation. And an open network drops the password field entirely rather than carrying an empty one, which is why a generator that leaves it in place can produce a code that phones refuse.

Which Security Type to Choose

Match the setting to the router and move on. The interesting rows are the bottom two, where the answer is that a QR code is the wrong tool rather than a setting to pick.

Enterprise Wi-Fi deserves the blunt version: if joining your network involves a username, a certificate or a device profile, a consumer Wi-Fi payload carries none of that and no generator can add it. Ask whoever runs the network how they onboard devices, and do not put staff credentials on a card.

Use the Guest Network, Not Yours

If the code is going anywhere the public can see it, put the guest network behind it. This is the one piece of advice in this guide I would argue with somebody about.

• The code is a readable copy of the credentials, so a sign in a window is a passphrase in a window. Put the network you are willing to publish behind it.
• Guest networks on most routers isolate clients, so a stranger who joins cannot see the till system, the network printer or the drive with your accounts on it.
• Rotating a guest passphrase costs you one reprinted card. Rotating your main one costs you every device in the building.
• You can hand a guest network a bandwidth cap or a schedule on plenty of routers, and neither of those is a thing you want to do to your own network.

The uncomfortable part, and the reason this matters more for Wi-Fi than for any other payload: a QR code is a readable copy of whatever is inside it. Nothing about the format is secret. A photograph of your window sign is your passphrase, in somebody else’s camera roll, for as long as they keep it.

Signs, and the Distance Each One Is Read From

Where the code goes decides how big it has to be, because size follows reading distance. A card people pick up is the easy case. A sign on a wall is not.

• Table tent or counter cardArm's length, roughly 30cmThe easiest case on this list, because people pick it up. Print the network name in text beside the code so somebody can join by hand when the scan fails.
• Wall or window signA metre or moreNeeds a much larger code than people expect, for the same reason a shirt does. Work the width back from the distance rather than guessing.
• Room card in a rentalIn the handAdd the checkout time and the bin day while you are printing. Nobody scans a Wi-Fi code twice, so put the code with the things they will re-read.
• Sticker on the routerClose, and awkwardFine for a home network, and the one place where writing the passphrase in text next to it is genuinely sensible.

Put the network name in readable text beside the code, always. Somebody will have a phone that will not cooperate, and a sign that offers no way through is worse than no sign. For the actual millimetres, work back from the distance using the print size guide, which is the same arithmetic a wall sign needs.

It Scans but Does Not Connect

Six symptoms, and in three of them the code is innocent. Work down the list in order, because the top two are the ones that are actually your fault.

When the code will not scan at all, rather than scanning and failing to join, that is a different problem with measured thresholds: why a QR code will not scan covers contrast, quiet zone and damage.

Check the Code Before You Print Fifty

The check that catches nearly everything takes a minute, and almost nobody does it: decode your own code and read the payload back.

1. 1Generate it with a temporary passphrase first, not your real one. If the tool turns out to be posting your text somewhere, you have leaked a throwaway.
2. 2Decode the finished image and read the string. It should begin with WIFI: and end with two semicolons, and every field should be what you typed.
3. 3Check the hidden flag is present only if the network really is hidden. This is the field people set by accident.
4. 4Regenerate with the real passphrase, then scan it on one Android phone and one iPhone. Platforms have disagreed about hidden networks and security types before.
5. 5Print one at final size, put it where it will live, and scan it there. A card on a sunlit windowsill is a different problem from a card on a counter.

Step two needs a decoder that shows you the raw text rather than acting on it, which is a different tool from a camera that helpfully joins the network and tells you nothing. The scanner guide covers which route reads a file on each platform.