Not a bug

Please educate me as to the correct lengths of months

stephen girman 5 years ago updated by Michael J. Radwin 3 years ago 2

I am not Jewish. I self-identify as Christian. I was exploring this calendar for my own edification, and to gain historical and cultural perspective.

I understand the odd numbered months to be 30 days in length, i.e. Nisan (01), Sivan (03), Av (05), Tishrei (07), Kislev (09), Sh'vat (11), and in leap years Adar I (13).

Conversely, the even numbered months are 29 days long, i.e. Iyyar (02), Tamuz (04), Elul (06), Cheshvan (08), Tevet (10), and Adar [ II } (12).

For the current year, 5779, I was counting the number of days from Rosh Chodesh to Rosh Chodesh for the entire year, and it seems your algorithm inverts the lengths of months, odd numbered months being 29 days, even months 30 days, excepting Adar I which seems to me to be 30 days.

Can someone help unconfuse me? Is my basic understanding incorrect, or is there an error in your algorithm? Thank you.

Please disregard my post. Mostly answered my own question by actually generating a calendar in *.pdf format. My confusion stems from some months indicating Rosh Chodesh both on the first day as well as last day of preceding month. The months not indicating two dates for Rosh Chodesh only indicate it occurring on the first day of the month. On the "Holidays" page, however, the dates for Rosh Chodesh all list the earlier date for months with two dates indicated, which in those instances is the last of the preceding month.

Should anyone stumble across my post, any enlightenment would be welcome.

I thank and commend the developers of Hebcal for, what seems to be to my ignorant eyes, this comprehensive set of tools.