Looking on the internet deeply has found these results:

Put in the calendar is the most popular phrase on the web.

Put on the calendar 17,990,000 results on the web	Put in the calendar 19,960,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
Absolutely. I will put that in my calendar. Erica put it in the calendar. If you need to talk to me, you call my office, and we'll get you put on my calendar. Let me tell you what we're going to teach Denise... when we put our calendars to work and set goals. Apparently, someone forgot to put it on the calendar. My assistant put it in my calendar for the week. Put that on my calendar, please. Try to put this on the calendar for tomorrow,	I put it on his calendar six months ago. Erica put it in the calendar. Absolutely. I will put that in my calendar. Try to put this on the calendar for tomorrow, My assistant put it in my calendar for the week. Let me tell you what we're going to teach Denise... when we put our calendars to work and set goals. Put that on my calendar, please. Apparently, someone forgot to put it on the calendar.

Put on the calendar

17,990,000 results on the web

Put in the calendar

19,960,000 results on the web

More popular!

Absolutely. I will put that in my calendar.
Erica put it in the calendar.
If you need to talk to me, you call my office, and we'll get you put on my calendar.
Let me tell you what we're going to teach Denise... when we put our calendars to work and set goals.
Apparently, someone forgot to put it on the calendar.
My assistant put it in my calendar for the week.
Put that on my calendar, please.
Try to put this on the calendar for tomorrow,

I put it on his calendar six months ago.
Erica put it in the calendar.
Absolutely. I will put that in my calendar.
Try to put this on the calendar for tomorrow,
My assistant put it in my calendar for the week.
Let me tell you what we're going to teach Denise... when we put our calendars to work and set goals.
Put that on my calendar, please.
Apparently, someone forgot to put it on the calendar.