To check the prices for the Eiffel Tower, please visit this page on the official Eiffel Tower site. The Eiffel Tower online ticket office provides the official prices.
The adult price applies to adults 25 years and over. There are discount rates for young people (12-24 years old), children (4-11 years old) and for visitors with disabilities and those accompanying them (maximum of one accompanying person per disabled person). Admission is free for children under 4 years old. The price of the ticket varies upon how you go up (elevator and/or stairs) and the destination (2nd floor or the upper floor) you select.