Thank you for your review
Email me when discounted: 
InterCal is a date conversion program and perpetual calendar. It is not a personal appointment calendar.

The program displays calendars, one month at a time, for any month of any year in any of nine implemented calendar systems. For each day, the corresponding date in any other system can be shown~thus an entire month is converted at once.

Any single day can be selected and its equivalent listed in all systems.Certain Christian, Jewish, and Islamic holydays can be highlighted if the user wishes.

The implemented systems are: Gregorian, Julian, Western Historical (hybrid Gregorian/Julian), Jewish, Islamic, Chinese, Mayan, more...

What's New

Version 2.2:
  • InterCal is now a Universal binary.
  • Otherwise it is identical to InterCal 2.1 with one minor exception. The starting point of the Chinese calendar has been changed by exactly one 60-year cycle, to agree with the (correct) results in the Classic version of InterCal (version 1.4.1 which is no longer supported)


Mac OS X 10.4 or later

Similar Software

Open Comparison
Suggest Other Similar Software
Leave a Review

InterCal User Discussion

Nobody has reviewed or commented on this app yet. Add your own comment and get a discussion going!
Sort by: Time | Smiles
Outer Member IconReview+118

Good to have it back without needing Rosetta under Lion. Admirably accomplishes what it promises - nothing more, but no less.

Reply0 replies
Version 2.2
Yazdgerd Member IconComment+0

You forgot to add the MOST CORRECT calendar system in the entire world. Persian Calendar is needed for this application.

Reply0 replies
Version 2.0
hisbonenus Member IconReview+1

It would be worth it just for the documentation. InterCal includes a fascinating manual that tells you about the algorithms used to generate the calendars, and the differences between them.

The program itself is great- very customizable. It's incredible to be able to see a calendar for any year you want.

Reply0 replies
Version 2.0
Anonymous Member IconReview

Works great, now anyone can be Rainman! Seriously, more useful than you might think. If you are a journalist, historian or even a historical-fiction author know the day of the week something happend can be important.

And being able to overlay other world calendars on top of the Western one is especially helpful in planning a trip or doing international business.

Would like to see note fields, time-lines tools etc. But it does what it claims.

Reply0 replies
Version 2.0
There are no Ratings for this App yet.
> 5 3


Current Version (2.x)


Downloads 3,888
Version Downloads 549
License Free
Date 03 Aug 2011
Platform OS X / PPC 32 / Intel 32
Price Free
Learn how MacUpdate Desktop makes installing apps from MacUpdate.com one-click easy.
Next time, install InterCal with 1-click

Learn how MacUpdate Desktop can install apps on MacUpdate with the simple click of the Install apps with MacUpdate Desktop icon. Plus, keep all your apps updated. Play video...