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Calendar Oddities

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About

Calendar Oddities checks whether today is a peculiar date — a leap day, a Friday the 13th, a palindrome, a solstice, a doubled day/month — or just an ordinary one.

How it works

Pure date arithmetic on today's Date: weekday/day/month tests, a palindrome check on the DDMMYYYY string, and approximate solstice/equinox dates. No backend.

Metadata
title
Calendar Oddities
description
Is today a strange date? Leap days, Friday the 13th, palindrome dates, solstices and doubled dates — what makes today odd, and what’s next.
canonical
https://kaspirius.com/calendar-oddities
updated
Last updated
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Structured data (JSON-LD)
TechArticle

Same as Article, flagged as technical/developer reference material.

{
  "@context": "https://schema.org",
  "@type": "TechArticle",
  "headline": "Calendar Oddities — ritual",
  "description": "Is today a strange date? Leap days, Friday the 13th, palindrome dates, solstices and doubled dates — what makes today odd, and what’s next.",
  "url": "https://kaspirius.com/calendar-oddities",
  "mainEntityOfPage": {
    "@type": "WebPage",
    "@id": "https://kaspirius.com/calendar-oddities"
  },
  "datePublished": "2026-06-18",
  "dateModified": "2026-06-18",
  "author": {
    "@type": "Person",
    "name": "kaspirius",
    "url": "https://kaspirius.com"
  },
  "publisher": {
    "@type": "Organization",
    "name": "kaspirius",
    "url": "https://kaspirius.com"
  }
}
↖ kaspirius