Khelifi made his professional debut on 6 August 2012 for Lausanne-Sport against Servette in a Swiss Super League match.

[2] He made his debut in the Bundesliga on 3 May 2014, replacing Karim Bellarabi in the 88th minute of Braunschweig's home game against FC Augsburg.

[6] In September 2022, Khelifi joined Australian A-League Men club Perth Glory on a one-year contract.

Perth Glory confirmed that it was not their decision to accept the loan offer, but they were instructed to do so by the Australian Professional Leagues (APL).

[9] Perth Glory was in administration at the time as attempts were made to find a buyer for the club, and they were also blocked from signing any new players or extending any loans.