The Gregorian calendar always bugged me - months of uneven length, names of the months not corresponding with their position. Sept,Oct,Nov,Dec - 7,8,9,10. I wondered if i was to design a calendar what would it look like.

Aptus is what I came up with — 13 equal 28-day months (not a new concept i know), anchored to the spring equinox instead of January 1. Not a replacement for Gregorian, just an alternative that tracks the actual solar cycles a bit more closely. It auto-detects your hemisphere, has a subscribable ICS feed so it layers onto whatever calendar you already use, and includes seven observance days derived from the real solstices and equinoxes rather than picked dates.

No signup, no monetization. I'm not a web developer — Claude Code is what actually turned this from an idea into a working site.