International Alpha Numeric Calendar (IANC) is the proposed reformed calendar inspired from International Fixed Week Calendar with 13 months of 28 days each except for the scond month. The International Fixed Calendar by Moses B. Cotsworth consists of 13 months of 28 days each, but additional days (1 in a normal year, 2 in a leap year) are not allotted to any weekday. In practice, weekdays from the 7-day cycle are continued without any interruptions. Therefore it is not possible of adding leap week, leap month, or zero weekdays etc. Similarly, the International Super Calendar also proposes slight modifications of the International Fixed Week Calendar. Also, Super calendar consists with two additional days, like Year day (Uran Day) and Leap day (NepDay).
The proposed IAN Calendar differs from the existing Gregorian Calendar as follows:
- The IAN Calendar has 13 months.
- In IAN, the second month has 29 days in a normal year, 30 days in a leap year.
- All months except second month have 28 days.
- Months are denoted by letters and days are denoted by numbers. This is called a alphanumeric notation.
The following table shows the names of the months and their starting dates in the Gregorian calendar.
| No. | Month name | Gregorian start date | Length |
|---|---|---|---|
| 01 | AN | January 1 | 28 |
| 02 | BO | January 29 | 29/30* |
| 03 | CP | February 27/28* | 28 |
| 04 | DQ | March 27 | 28 |
| 05 | ER | April 24 | 28 |
| 06 | FS | May 22 | 28 |
| 07 | GT | June 19 | 28 |
| 08 | HU | July 17 | 28 |
| 09 | IV | August 14 | 28 |
| 10 | JW | September 11 | 28 |
| 11 | KX | October 9 | 28 |
| 12 | LY | November 6 | 28 |
| 13 | MZ | December 4 | 28 |
| Total | 365/366 | ||
| * - Leap Year | |||
IAN Calendar 2025[]
| Sun | Mon | Tue | Wed | Thu | Fri | Sat |
|---|---|---|---|---|---|---|
| 01 | 02 | 03 | 04 | |||
| 05 | 06 | 07 | 08 | 09 | 10 | 11 |
| 12 | 13 | 14 | 15 | 16 | 17 | 18 |
| 19 | 20 | 21 | 22 | 23 | 24 | 25 |
| 26 | 27 | 28 |
| Sun | Mon | Tue | Wed | Thu | Fri | Sat |
|---|---|---|---|---|---|---|
| 01 | 02 | 03 | 04 | |||
| 05 | 06 | 07 | 08 | 09 | 10 | 11 |
| 12 | 13 | 14 | 15 | 16 | 17 | 18 |
| 19 | 20 | 21 | 22 | 23 | 24 | 25 |
| 26 | 27 | 28 | 29 |
| Sun | Mon | Tue | Wed | Thu | Fri | Sat |
|---|---|---|---|---|---|---|
| 01 | 02 | 03 | ||||
| 04 | 05 | 06 | 07 | 08 | 09 | 10 |
| 11 | 12 | 13 | 14 | 15 | 16 | 17 |
| 18 | 19 | 20 | 21 | 22 | 23 | 24 |
| 25 | 26 | 27 | 28 |
Date Format (yyyy-MM-dd)[]
The date format is alphanumeric with the month always being represented by two Latin letters.
- 2025, January 1 -> 2025-AN-01
- 2025 June 30 -> 2025-GT-12
- 2025 December 31 -> 2025-MZ-28
Serial Date Number and Week[]
Serial Date (1-365/366*) is calculated from IANC easily as follows.
Let M=Month, D=Date, T= Serial Date Number, W= Week Number in IANC
If M<=2,
T=28*(M-1)+D
W=4*(M-1)+ Integer ((D-1)/7)+1
If M>2,
T=28*(M-1)+D+1+L
W=4*(M-1)+ Integer ((D+L)/7)+1
where, L=0 in Normal Year, 1 in Leap Year.
Advantages[]
- In Gregorian calendar, 7 months have 31 days, 4 months have 30 days, and one month has 28/29* days which are the complex structure. But in IANC, All months (12) except second month have 28 days. These months have exactly 4 weeks. Months from 3 -13 are identical.
- All dates in IANC (Except two days in February last) are permanently fixed to Current Gregorian Calendar. So the two calendars are parallelly used.
Limitations[]
- The Year can be divided as Quarters for 13 weeks each. But the months are not fully fit in quarters.
- Seasons are fit in various dates as follows (Apparently):
- Vernal Equinox - CP 23 (March 21)
- Summer Solstice - GT 24 (June 22)
- Autumn Equinox - JW 13 (September 23)
- Winter Solstice - MZ 19 (December 22)