Klonaridis emerged from the AEK Athens academy as a young prodigy, signing his first professional contract with the club at the age of 18.

[4] On 3 August 2013, Panathinaikos paid to AEK Athens €1 million for his transfer (just like with Georgios Koutroumpis the same summer) and Klonaridis signing a 4-year contract with the "Greens".

[12] On 31 August 2016, the last day of the summer window transfer, Klonaridis returned to France, signing a two-year contract with Ligue 2 club Lens, for an undisclosed fee.

[14] On 31 May 2017, his goal and overall positive performance, helped his club to succeed an away 3–2 win against rivals PAOK in the last matchday of the 2016–17 Playoffs depriving them of the possibility to participate in the UEFA Champions League third qualifying round.

[19] On 16 September 2018, Klonaridis scored his first brace with the club in a 4–0 home win game against Panionios, as six minutes from full time with a brilliant piece of individual skill, skipping past the challenge of Luis Gustavo Dominques before firing a powerful shot beyond Panthers goalkeeper Filip Manojlović and at the last minute of the match scoring his second of the night, slotting home after good work from striker Marko Livaja.

In both goals, he scored with a right footed shot from very close range after assisted by Niklas Hult and Marios Oikonomou respectively, but after the AEK forward missed a great chance for his hat-trick, Alfa Semedo's long-range strike won it for Benfica on the counterattack.

[22] On 1 March 2020, Klonaridis scored a stunning goal in stoppage time to salvage a thrilling 1–1 away draw for AEK against Panionios.