CDG to gare est Paris transport

Flat fee taxi from the official taxi queue at CDG. €56 or

RER B to Gare du Nord, then walk about 10 minutes to Gare de l'Est

Where are you going from Paris Est? You might have direct train there from CDG.

You may be aware, but it is worth pointing out that there are three main train stations in Paris. I assume that you are looking for Gare De l'Est. As someone else pointed out, you may be able to get a good train connection directly from CDG. However there was some trainline construction near CDG this past May right during the travel season that disrupted transit from the airport and elsewhere in France for that matter. Double check your ticket if you go by train. I was badly impacted by construction, and I would suggest you check that your ticket was issued by SNCF, and not by a reseller.

I count 6 major train stations and a couple of minor ones in Paris so yes you do have to be pretty specific.

Where are you headed from CDG? Six major train stations altogether: Gare de l'Est, Gare Austerlitz, Gare Saint-Lazare, Gare Montparnasse, Gare du Nord, Gare de Lyon. Destination determines which station you need.