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Unrecognized QR code when scanning

See original GitHub issue

I used to generate QR codes for my app. Here is an example output:


Authenticator says “Unrecognized QR code.” when I try to scan it, however using Google Authenticator app to scan the code works fine. I can also decode it using and it says the parsed result is:


This looks valid to me.

In fact, when I take the above URL and put it into and then scan the output QR code with Authenticator, it works! There’s something about the above QR code that’s not working with Authenticator for some reason.

Issue Analytics

  • State:closed
  • Created 5 years ago
  • Comments:5 (3 by maintainers)

github_iconTop GitHub Comments

mymindstormcommented, Apr 12, 2018

This reader and the error I’m getting from jsqrcode, Invalid mode: 7 in (block:0 bit:3), seem to say that it’s in ECI mode 7. According to the code you have it should be 26, so jsqrcode may just be reading the ECI data wrong.

That patch I found seems to work just fine. It should work with 5.0.10

multiwebinccommented, Apr 12, 2018

Are you sure the ECI mode is set to 7? According to, the above QR code uses UTF-8 character set, which also coincides with what was requested during QR generation, not ECI mode 7 (which would be ISO/IEC 8859-5).

Also, looking at the code for BaconQrCode it looks like they have taken these various encodings into account, so it would seem likely that the error is not with that package but instead with jsqrcode. Unfortunately it looks like jsqrcode is no longer being maintained.

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