CALENDAR INSIGHTS · DATE DISCOVERIES · GUIDES
Curiosity, with an explanation.
Explore the mathematics, check a discovery, or find a thoughtful way to share it.
Calendar insights
Why some dates always land together
A seven-day rhythm can connect two birthdays through every calendar year.
Calendar insightsThe leap-year boundary
Why February divides the calendar into two useful segments.
Calendar insightsA birthday is not a birth weekday
Two similar-sounding facts answer different questions.
Date discoveriesJune 29 and August 24: eight weeks apart
A worked example you can check with any calendar.
Calendar insightsA birthday outside the ordinary groups
How we explain leap-day birthdays without forcing a false match.
GuidesHow to check a calendar connection yourself
A short method for separating a durable pattern from a coincidence.
Calendar insightsWhat the A and B groups mean
Fourteen labels organize dates without giving them mystical significance.
GuidesShare a discovery, start a conversation
A small invitation can be the beginning of something personal.
GuidesMake a free digital gift personal
The discovery opens the story. Your message gives it meaning.