[zouhair]

Just a note, xkcd has 2 image sizes.

Small: https://imgs.xkcd.com/comics/confidence_interval.png

Big: https://imgs.xkcd.com/comics/confidence_interval_2x.png

Though not for older ones.

[eryb]

Thank you for pointing this out, I didn't about it. How did you come to know? It isn't on their API info page.

[zouhair]

Webpage Source code.