Here is a list of some of the most high-profile free agents:
Goalkeepers:
Keylor Navas - Costa Rica, 37 years old
Loris Karius - Germany, 31 years old
Tomas Koubek - Czech Republic, 32 years old
Etrit Berisha - Albania, 35 years old
Defenders:
Sergio Ramos - Spain, 38 years
Marcelo - Brazil, 36 years
Adama Soumaoro - France, 32 years
Ghislain Konan - Ivory Coast, 28 years
David Luiz - Brazil, 37 years
Daniel Amartey - Ghana, 29 years
Kyriakos Papadopoulos - Greece, 32 years
Wallace - Brazil, 29 years
Koffi Djidji - Ivory Coast, 31 years
Serge Aurier - Ivory Coast, 31 years
Mário Fernandes - Russia, 33 years
Cedric - Portugal, 33 years
Bouna Sarr - Senegal, 32 years
Filip Benkovic - Croatia, 27 years
Layvin Kurzawa - France, 31 years
Simon Kjaer - Denmark, 35 years
Midfielders:
Dele Alli - England, 28 years old
Christoph Kramer - Germany, 33 years old
Marco van Ginkel - Netherlands, 31 years old
Hector Herrera - Mexico, 34 years old
Antonio Candreva - Italy, 37 years old
Roque Mesa - Spain, 35 years old
Paul Pogba - France, 31 years old (suspended until March)
Rafinha - Brazil, 31 years old
Eduard Michut - France, 21 years old
Samu Castillejo - Spain, 29 years old
Francis Coquelin - France, 33 years old
Forwards:
Wissam ben Yedder - France, 34 years old
Diego Costa - Spain, 36 years old
Anthony Modeste - France, 36 years old
Mislav Orsic - Croatia, 32 years old
Stefano Okaka - Italy, 35 years old
Kevin Gameiro - France, 37 years old
Mattia Destro - Italy, 33 years old
Ryan Kent - England, 27 years old
Santi Mina - Spain, 28 years old
Maxi Gomez - Uruguay, 28 years old
Mariano Diaz - Dominican Republic, 31 years old