A bit more context for those who don't knit or know much about QR codes: A knitting pattern consists of a lot of text (and in this case, also a chart) so it's not feasible to encode the pattern itself into a QR code small enough to fit on a mitten. Compare these two QR codes. One is 25x25, and one is 29x29. The bigger one points to the actual URL for the mitten pattern (https://www.web-goddess.org/mittens.php), while the smaller one is using the goo.gl shortener to redirect to that same URL. I had to switch to a much thinner wool to knit the QR code at a resolution that would fit on the mitten (and would actually scan), so I needed the shortest URL/smallest code that would fit. In retrospect, I shouldn't have trusted Google. Lesson learned!