{"product_id":"13-month-time-system-calendar-international-fixed-calendar-explained-433884578","title":"13-Month Time System Calendar – International Fixed Calendar Explained","description":"\u003cp\u003eThis 13-Month Calendar presents a structured and symmetrical approach to measuring time, based on the International Fixed Calendar concept.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eDeveloped by Moses B. Cotsworth and introduced in 1902, this calendar was proposed as a reform of the traditional Gregorian system. It is also known under several names, including the Cotsworth Plan, Eastman Plan, and Yearal.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eUnlike the modern calendar, this system organizes the year into 13 uniform months, each made up of 28 days. Every month contains exactly four weeks, resulting in a stable and predictable layout where weekdays never change from year to year.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eHow the 13 Month Calendar Works:\u003c\/p\u003e\u003cp\u003e• 13 months per year\u003c\/p\u003e\u003cp\u003e• 28 days in each month\u003c\/p\u003e\u003cp\u003e• 4 weeks per month\u003c\/p\u003e\u003cp\u003e• Total of 364 days\u003c\/p\u003e\u003cp\u003e• One additional “Year Day” outside the weekly cycle\u003c\/p\u003e\u003cp\u003e• Leap years include an extra leap day\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eThe extra month is traditionally called Sol and is placed between June and July.\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eMaterials: birch plywood 3 mm\u003c\/p\u003e\u003cp\u003eColors:  rosewood, old oak\u003c\/p\u003e\u003cp\u003eDimensions: M - 30\u0026amp;khcy;22,5 \u0026amp;scy;m\/ 11.8x8.7\";  L - 30\u0026amp;khcy;40 \u0026amp;scy;m\/ 11.8x15.8\"\u003c\/p\u003e\u003cp\u003ePersonalization on the back side at the bottom right\u003c\/p\u003e\u003cbr\u003e\u003cp\u003eWhy This Calendar Is Unique:\u003c\/p\u003e\u003cp\u003e• Perfect monthly symmetry\u003c\/p\u003e\u003cp\u003e• Consistent weekly structure\u003c\/p\u003e\u003cp\u003e• No shifting weekdays from year to year\u003c\/p\u003e\u003cp\u003e• Historically proposed as a global calendar reform\u003c\/p\u003e\u003cbr\u003e\u003cp\u003ePerfect For:\u003c\/p\u003e\u003cp\u003e• Calendar and history enthusiasts\u003c\/p\u003e\u003cp\u003e• Educational displays and learning spaces\u003c\/p\u003e\u003cp\u003e• Office, study, or library décor\u003c\/p\u003e\u003cp\u003e• Unique gifts for thinkers and planners\u003c\/p\u003e\u003cp\u003e• Conversation-starting wall art\u003c\/p\u003e\u003cbr\u003e\u003cp\u003e📌 This calendar is presented for educational and decorative purposes. It is not an official calendar system in modern use.\u003c\/p\u003e","brand":"Esoteric Wings","offers":[{"title":"M with pers \/ Rosewood","offer_id":52798337351991,"sku":"143-2","price":42.0,"currency_code":"USD","in_stock":true},{"title":"M with pers \/ Old oak","offer_id":52798337384759,"sku":"143-2","price":42.0,"currency_code":"USD","in_stock":true},{"title":"M without pers \/ Rosewood","offer_id":52798337417527,"sku":"143-2","price":32.0,"currency_code":"USD","in_stock":true},{"title":"M without pers \/ Old oak","offer_id":52798337450295,"sku":"143-2","price":32.0,"currency_code":"USD","in_stock":true},{"title":"L with pers \/ Rosewood","offer_id":52798337483063,"sku":"143-2","price":58.0,"currency_code":"USD","in_stock":true},{"title":"L with pers \/ Old oak","offer_id":52798337515831,"sku":"143-2","price":58.0,"currency_code":"USD","in_stock":true},{"title":"L without pers \/ Rosewood","offer_id":52798337548599,"sku":"143-2","price":48.0,"currency_code":"USD","in_stock":true},{"title":"L without pers \/ Old oak","offer_id":52798337581367,"sku":"143-2","price":48.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0983\/3549\/0359\/files\/38247f03-f7ea-4234-8977-176fe7d3907d-copy.jpg?v=1786080850","url":"https:\/\/esotericwings.com\/products\/13-month-time-system-calendar-international-fixed-calendar-explained-433884578","provider":"Esoteric Wings","version":"1.0","type":"link"}