Calendar Cleaner analyzes, reports, and fixes dozens of problems with OS X Calendar and Apple Sync Services—problems ranging from the obvious, such as duplicated events, to the subtle, such as invalid calendar dates and alarms.

If you're like us, your calendar is how you manage your life. And that means that bad data can mean a really bad day—or worse. Calendar Cleaner removes duplicates, finds subtle problems with your events, and keeps everything clean as a whistle.

For more information, tips, and a FAQ, see:

*** Feedback from Users of Calendar Cleaner ***

"I adore Calendar Cleaner, by the way. It saved me the trouble of manually filtering through nearly 30,000 calendar records, dating back to 1999, to remove about 3,000 duplicate records that had been created by sync misfires over the last 10 years of Palm and Mac OS syncing." —Don N.

"Calendar Cleaner: LOVE LOVE LOVE this tool. It's saved me hours of headache and heartache." —Rich S.

"Just dropping by to say good job! it works great! I've been having some issues with a self-duplicating calendar event and it cleaned it up! Syncing now is normal and trouble free." —David C.

"Very nice tools! Great scan speed for iCal events!" —Jochen W.

What’s New

Version 1.7.2

* Bug fixes
* Minor UI tweaks
* New app icon
* Rebranded part of "Cleaner Tools for Mac"

New in version 1.7.1:
* Faster! Faster! Faster!
* Various UI enhancements and bug fixes

Ratings and Reviews

Redbudgroup ,

a bridge too far

I don't know how I got one birthday announcement fighting with a second announcement trying to ring the bell at the same time...but...The announcement then propagated themselve to EVERY day in my caledar. Removing the birthday person from my "Contacts" was the beginning of the fix and I still had a lot of cleanup. Somewhere in my thrashing path to solution All of my color references vanished and the result was a black and white calendar...sad. Perhaps it was that I had moved onto Mojave. At any rate this app created a lot duplicate entries in both my "Contacts" file and my calendar.

@seabirds ,

Not very impressed

I purchased this app based on a recommendation from the Applecare tech guy. I fully understand that they are not responsible for the quality of the app as they did not write it. My problem was that I had many duplicate appointments after transferring my mail from Outlook to the Mac calendar. I did the download while my Mac guy was viewing my screen, so I think I did what I was supposed to do in installing and running it. It is actually very simple and difficult to make a mistake and I am no novice in software use. I suspect there is a bug in the app as after I ran it, not only did it not delete duplicate appointments, but it multiplied them, actually scheduling ALL of my appointments to occur every day out to the limit of the calendar! With the help of the tech, I was able to delete all appointments in the calendar and from the cloud, restore the calendar to what it was earlier that day. I would say that it may have been something in my system that caused it because no one would buy it if all had my experience. I would recommend that the designers take a look and fix it.

Kellya74u ,

Problem App is not updated since 2014-emails to support-bounce

I purchased this & contacts cleaner, really wanted & needed to like these apps. However, used the calendalr cleaner scan once, yielding a list of “bad” calendar dates. Clicking ‘fix’ deleted them from the actual day, & instead populated the calendar item 6-8 times a day, every day, for years past & in the future. Spent 6hrs deleting the additionally bad data the app created. That was last year, 2018. I searched my computer for an item & found a calendar entry with that name, clicked on the icon, which took me to 2042, 6 entries per day, every day for months going forward. Stopped looking because I’ll be dead then. There are PDF guides downloadable from the website, but unknown if the app(s) guieds work as intended 5yrs ago with no updates.

Emailed customer support which immediately bounced back as a (currently) nonexistent email. Deleted Calendar Cleaner & Contact Cleaner from my computer. I do not recommend.


Aston Shaheen
1 MB

OS X 10.7 or later, 64-bit processor



Age Rating


  • Family Sharing

    With Family Sharing set up, up to six family members can use this app.