CDG airport

2 hours should be OK. 90 min can be tight.

Check your connection transfer:
http://www.easycdg.com/1/informations-passagers/connecting-flight-connections-guide-paris-cdg-airport/connection-terminal-2e-paris-cdg-charlesdegaulle-airport/

Looks like Air France PRG departs from 2F.

It all depends on the number of flights arriving at the same time and the attitude of the passport inspectors and security personnel you encounter that day. We missed a connecting flight from CDG to Luxembourg in May 2011 for one or both of these reasons even though we had more than two hours between flights. But, if you do miss the connecting flight, go immediately to the AF office at CDG. They put us on the next flight out, so all was not lost.

Edgar, you are right. The flight does leave from 2F (I was looking at the wrong flight). Thanks for pointing that out!

Roy, thanks for the tip!

If your flight from Miami lands on time you're unlikely to have a problem. If it's delayed, Air France will take care of you as long as the flight to Prague is on the same itinerary.

...attitude of the passport inspectors and security personnel...

We had a 90 minute connect a few years ago and nearly missed our flight. The unusual circumstance was having to deplane away from the terminals, getting bussed to a remote passport control/security screening building then needing to get bussed to the regular terminal. We had to wait for a second bus.

Another passenger had an even tighter connection departing 5 or 10 minutes before our connection. This passenger started "yelling" at the French ground staff. At worst the French slowed down and at best they didn't care.

I was referring specifically to male passport control agents who flirted with every pretty girl in line. That can slow things down considerably when you are on a flight with a tour group of high school and/or college girls; not only did it cause us to miss our flight, but my wife was offended that they passed her through without a word.

My connection two weeks ago was 1 hour between 2e and 2f and we had no problems. All the personnel we encountered were polite and efficient. Look up the later flights so you know the possible options and that should help your peace of mind. Say bonjour to people you will interact with before you say anything else. That should be the first paragraph of the RS france guides! I forgot to say it once and got a quick lesson in French manners from the irritated security agent, but he still helped me out quickly and wished me Bon voyage.

Regarding the yelling man, One thing I hated to witness on my trip is how rude some of my fellow Americans are--expecting others to be their servants and treating them as such, rather than as equals. The yelling man probably got the unhappy trip he created for himself with that attitude.

If your connection is really tight, you can ask to use the First Class/Business Class line at Passport Control, which goes much quicker. I have done this several times at CDG and if you are polite, it works.

Thanks everyone!