Hand‑drawn QR codes — Seth Larson

I really like QR codes. Recently I purchased a new sticky-note-like
pad from a new local stationery store in Minneapolis.
The sheets have a 10×10 grid and 2×10 grid.

I knew what I wanted to do, I wanted to create a QR code on a sheet.
The smallest QR code (besides micro QR codes) is “version 1” which uses 21×21 pixels.
We’ll have to split the squares in half and then use some of the margin.

Version 1 QR codes can hold URLs up to 17 bytes long using the lowest
data quality setting. Unfortunately https://sethmlarson.dev is 23 bytes
long, so I’ll have to improvise. I went with sethmlarson.dev instead, as this
will prompt many QR code scanners to “search” for the term resulting in my website.

Note that a lovely reader informed me shortly after publication that indeed
I can include my full domain name in a version 1 QR code by using all capital
letters instead of lowercase. TIL that the “alphanumeric” character set for QR
codes actually contains symbols for URLs like : and /.

Expect an updated QR code published after lunch today. 🙂

I created my reference using the qrcode package on the Python Package Index. Don’t forget
the -n option with echo to not include a trailing newline.

$ echo -n "HTTPS://SETHMLARSON.DEV" | qr --error-correction=L

I drew the corner squares (known as “position patterns”) and then started trying
to scan the QR code as a gradually filled in other pixels. Once I had drawn the
“timing lines” between the top left and bottom left position I could
see that my scanner “wanted” to see something in my drawing.

I continued adding the top timing line and data and then the scanner could
start to see the whole square as a QR code. If you look closely I even
made a mistake here in the data a bit, but in the end this didn’t matter
even on the lowest error-correction level.

Finally, my QR code was complete! Scanning the QR code was quite finicky because
the paper was curling up off the flat surface. I could only get the scan to work
when I held the paper flat. However, hanging the QR code from my monitor worked
extremely well, even when scanning from a distance.

I hope this inspires you to try hand-drawing something on grid paper 🖤🤍
If you’re looking for more grid-based inspiration, take a look at GRID WORLD, a web art piece by Alexander Miller.

Wow, you made it to the end!