You can view the estimated fare on the app just before confirming the booking:

[![enter image description here][1]][1]

Alternatively you can use one of the many fare estimator websites out there, including [uber's own one][2] which says that the fare is 45 EUR with UserX or Green:

[![enter image description here][3]][3]

As it turns out, this is to date [the flat fare from CDG into Paris][4].


  [1]: https://i.sstatic.net/B29eGl.png
  [2]: https://www.uber.com/en-FR/fare-estimate/
  [3]: https://i.sstatic.net/9sWZIm.png
  [4]: https://www.uber.com/airports/cdg/