Closed why are the QR codes so much larger?


diabolic1

Member
Oct 29, 2020
5
0
Daniel,

I notice that the QR codes generated by the wordpress plugin are much larger than on this forum. I assume this is because of error correct or some other format, but it'd be great to use smaller QR codes so they are easier to scan. Any ideas?
 

PHolder

Well-known member
May 19, 2018
1,207
202
The size of the QR Code is related to the amount of data being encoded within. The WordPress URLs must be longer, or have more parameters. (The size of the site name is also a part sqrl.grc.com is practically the smallest possible site name, because grc is only three letters.)
 

diabolic1

Member
Oct 29, 2020
5
0
I don't think that's it. The nuts appear to be the same size. The URL is only a few characters longer. I suspect there are multiple ways of encoding QR with varying levels of error correction. I'll ping Daniel offline.
 

PHolder

Well-known member
May 19, 2018
1,207
202
I just captured a sample URL from the sarah site and it is (char counts) (sqrl:// 7) (sarah.gives/ 12) (wp-admin/ 9) (admin-post.php? 15) (action=sqrl_auth& 17) (nut=... & 37) (can=... 30) for a total length of 127 characters. A sample SQRL URL from this site is: (sqrl:// 7) (sqrl.grc.com/ 13) (cli.sqrl? 9) (x=1& 4) (nut=... 16) for a total of 49 chars. If you can make sense of the tables at https://www.qrcode.com/en/about/version.html#versionPage1_10 you can see the minimum size of 49 chars is type 3 and for 127 chars is type 5. If you want more redundancy, then it will require even larger QR codes respectively.

FYI the NUT sizes are not really that close to comparable at 16 versus 37.
 
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Chauncy

Member
May 30, 2018
5
1
it'd be great to use smaller QR codes so they are easier to scan. Any ideas?
If i remember correctly, some phones had trouble with smaller QR codes during development. If you hover the mouse cursor over the QR codes generated here you will notice that they get larger and the cursor disappears. This allows for more reliable scanning.
 

diabolic1

Member
Oct 29, 2020
5
0
If i remember correctly, some phones had trouble with smaller QR codes during development. If you hover the mouse cursor over the QR codes generated here you will notice that they get larger and the cursor disappears. This allows for more reliable scanning.
A smaller QR code at a fixed size is actually easier to scan than a larger QR code with more bits and thus smaller features. In any case, I'm closing this because I got the answer I was looking for. Thanks!