Printable calendar

Every month is laid out as six rows of seven even when five would fit. That is deliberate: a month whose grid changes height between pages looks wrong when the sheets are pinned up together, and some months genuinely need six rows — a 31-day month starting on a Saturday spills into a sixth week. Fixing the row count keeps every page identical.

The week-start setting is not cosmetic. ISO 8601 and most of Europe start the week on Monday; the United States, Canada and Japan start on Sunday. Get it wrong and every date sits in the wrong column, which is the sort of error nobody spots until the calendar is on the wall.

Week numbers follow ISO 8601, where week 1 is the week containing the first Thursday of January. That means week 1 usually begins in the previous December — the first days of January can belong to week 52 or 53 of the year before. It looks like a bug and is correct, and it is why the numbers only make sense alongside Monday-start weeks.

The output is vector PDF at true page size, so it prints crisply at any scale and the margins are right on A4 and Letter. A calendar exported as an image prints soft and often at the wrong size, because the browser has to guess a DPI.