We will be arriving in Paris on Friday Dec, 5th midmorning. We are a well travelled elderly couple, first time in Paris. As a result of previous misadventures trying to get to/from an airport we generally prefer taxi as it is reliable without being outrageously expensive. Any reason why this wouldn't work this time? Is the fare metered or fixed? Is the taxi stand easy to find and is there likely to be a long line? The train is appealing from a cost and speed point of view but would involve a bus connection or 15 minute walk to our hotel either of which could challenge our jeg lagged selves. I found several pre-booked services on line at quite variable prices, but hard to tell if they have any advantage over the wait-at-the-curb option.

Paris taxis have a fixed rate from CDG. If I am not mistaken (and assuming it has not been updated again), right bank is Euro 56 for the right bank, Euro 65 for left bank. 5th Arr. is on the left bank. I doubt you will find pre-arranged transport for much less than those rates.

Travel Nerd has it right.

If you google « CDG taxi » the AI explanation is succinct:

>>A taxi from Charles de Gaulle (CDG) to central Paris has fixed rates of €56 for the Right Bank and €65 for the Left Bank, which includes up to four passengers and luggage. To find an official taxi, follow the signs to the designated taxi stands located outside each terminal's arrivals exit, and do not accept rides from unsolicited drivers inside the terminal.
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You may also refer to the website for CDG for more info.

Thank you both; that is exactly the information I need. My Google search was so cluttered with ads from private companies I couldn't find what I was looking for.

Its very wise to get a taxi if you are an older couple.. We are (64 and 72) and took the train from CDG to the 5th last October.
It is really very easy, but we had to change at Les Halles subway station and that was a little bit harder and confusing.

And at the airport do not fall for any tout who approaches you. You will find on this site and other travel Q&A sites that you must ignore them and get a taxi from only the official taxi line. It can be long but moves fast. Some recommend to have the address of your destination including the arrondisement like "75006" for the sixth written down on a piece of paper with also "65 Euro" written on it so no iquestion the driver knows you know about the fixed fee.

Thank you, yes, we definitely will avoid anyone approaching us with offers. We are both in our 80's and I am hearing impaired so easily confused. I like to have printed copy of all reservations.so adding the cost of an airport taxi in euros is a great idea. We don't speak French but as Canadians we know enough to read signs which should help when we are out and about. Most of our time is on a short Seine cruise with GCT but we do have some time at beginning and end to fend for ourselves.

Paris is so easy BUT I always say “take a taxi”. It’s easy, affordable, and again EASY.
The Metro and trains are fine but if you are there for a short time and unfamiliar, it’s too much work and walking,.
Look up where the taxi stands are close to where you are and do that.
Airport official taxi lines are short and move fast.

Eliz,
Taking a taxi is by far your best option. Octogenarians dealing with luggage during a transfer is reason enough.
We were just there and can recommend the following taxi driver Kwame. I am copying below the exact info from his card:
'Societe de Taxi (Gnamien) 06 84 47 03 31'.

We used him twice and will use him again this winter to take us to and from the 5e. No probs. One could ask about his little son Isaiah.
Good luck.
I am done. The end.