|Full name||Nikolaos Karelis|
|Date of birth||24 February 1992|
|Place of birth||Heraklion, Greece|
|Height||1.78 m (5 ft 10 in)|
|Playing position||Winger / Second striker|
|* Senior club appearances and goals counted for the domestic league only and correct as of 18 December 2014.
† Appearances (Goals).
Karelis made his professional debut the season 2007–2008 the last fixture (30th) of the Greek Super League, on 20 April 2008, entering as a second-half substitute (78 minute) in Ergotelis' 2–0 victory over Skoda Xanthi. Karelis became the youngest player to play for Ergotelis in a Greek Super League game.
Karelis had impressed Arsenal scouts as he had been invited to London to take part in a 10-Day trial started 29 April 2008 and at Atalanta U-16 Cup Tournament (Italy) where he scored 2 goals for the Gunners and had left very good impressions after helping Arsenal win the Cup beating Juventus in the final on penalties. He was determined to show his quality to the Gunners, but the transfer paused until he become 18 and he returned to Ergotelis F.C. for the season 2008/2009. Karelis made his first appearance the season 2008–2009 for Ergotelis, the last fixture (30th) of the Greek Super League on 26 April 2009, entering as a substitute (87 minute) for Patrick Ogunsoto in Ergotelis' draw 1–1 against A.E.K. Athens.
On July 2012 he signed with Russian Premier League side Amkar Perm. Karelis spent most of the season playing as a substitute.
On 30 July 2013 Karelis signed for Panathinaikos a three-year contract. He made his debut with the club on 18 August 2013 in a 2-0 home win against Panetolikos and on 24 November 2013, he scored his first out of two goals with the club in a 3-1 home win against PAS Giannena. On 26 April 2014, he scored the third goal in his first title of his career in a 4-1 win against PAOK in the Greek Cup final.  
Karelis has represented Greece with the youth teams.
- "Stats Centre: Nikos Karelis Facts". Guardian.co.uk. Retrieved 2009-03-18.
- "PAOK-Panathinaikos 1-4". 26 April 2014.
- Τα καλύτερα από τον τελικό Κυπέλλου (in Greek). 26 April 2014.