6 Days Trip to Rome; too much?

You need to provide more detail.

Do you mean, you plan 6 days in Rome, as part of a longer trip to Italy? (to me, that sounds great)
or...
Do you mean, you're going all the way to Europe and just planning 6 days, which you will be spending all in Rome? (to me, that sounds insane).

Have you been to Europe or Italy before? If part of a larger trip, to where and for how long?
Does that "6 days" include the days you spend getting there and departing from there? If so, from where are you coming, and where do you go after?

Details make all the difference.

6 days in Rome would be perfect for me but I love the city and hae been many, many times however there are people wh don't share my enthusiasm, just as I'm not enthused about Barcelona or Paris there are many who are.

We don't know you so it's impossible to suggest whether 6 days would be too much for you. What has your research suggested?

Yes we need more details. Count your trip as nights, not days
Is that 6 nights (which really equals 5 days) or is it 7 nights (6 days)

Rome sights alone can't be covered in just 6 sightseeing days. Most take a large chunk of time to see
Colosseum- better part of a day
Vatican/St Peter's - better part of a day
Then add in other sights- count maybe 2 a day- Pantheon, Borghese, Capitoline or whatever other museums/churches etc you want to visit and you can easily fill 4 solid days.

Again- more details needed but if you only have 5 full sightseeing days and have never been to Rome I see no need for any day trips.

Take a look here for itinerary ideas:
https://www.ricksteves.com/europe/italy/rome-itinerary

Thank you all for your amazing replies. Yes I am coming to Europe (from Cairo, Egypt) to visit Rome, I have travelled to Europe before but not to Italy.

I am going for a 6 day, 5 nights trip to Rome

Personally, five days would be getting started for us. Over the years we have spent close to a month in Rome and still have things we want to see on the next trip. I would say you can get a good overview in that time period.

In that case spend all of your time based in Rome, as there's more than enough to do in Rome alone. If you want to take a day trip during your stay, either Orvieto or Ostia Antica would be a good choice.

It's too much if you don't research your options and decide even vaguely how to spend your time.
It's too much if you aren't prepared to spend the time being independent and not looking for people to hang out with.
It's too much if you prefer a quick overview, tick off the Colosseum and the Vatican, drive around the city in the HoHo bus and decide that's enough.
It's not enough if you have an interest in history, art, architecture, parks, or places to go to from there.
What about gladiator school? Biking the Appian Way - your consideration of Florence for a day. You can even do Pompeii in a day.

You won't scratch the surface in that amount of time. Rome is an amazing city! If you do feel you need a break from it , there are some places to visit for a break from the congestion. None are a great distance from the city proper. Ostia Antica, Appenia Way, Villad'Este in Tivoli or Orvieto

My husband and I spent 6 days in Rome a few years back and had plenty to do and see along with just wandering the city. We did the usual, Colosseum, Vatican and Vatican Museum, took a day trip to Naples and Pompeii. We prefer not to have every minute booked with things to do and find time to just wander and see what we find. There were so many things to do and see, we are now going back this year with our kids and plan to do the things we didn't get to do the first time. I guess throwing the coin in the Trevi fountain really worked for us.

Rome in 6 days? I bet you'll be planning your return trip before you leave! July is going to be hot and humid so plan your days around breaks. The Italians will help you with that - the riposo in the afternoon is a great time to catch a nap, take a shower and head out for the (hopefully) cooler evening. Maybe now you should start going through books (like RS's) and make a list for yourselves of "must", "wanna" and "if we have time". My guess would be you can see/do inside things in the morning and maybe late afternoon. Save the evening for the outdoors things on your list. If you are into opera or ballet, the Rome Opera is in residence at the Baths of Caracalla. A very unique experience. Roaming around neighborhoods (my favorite roams in Rome is Trastevere, Piazza Navona, the Roman Forum. My apologies for the pun. There is much to see and do! A great day trip is to Ostia Antica or even the city of Orvieto. Don't wear yourselves out - Rome has been there for thousands of years, you can always come back!