According to Official Guinness Records,
The largest single edition of a magazine is 7.591 m² (81.71 ft²) and was created by Warner Bros. Ent. France (France), and presented at Grand Rex, Paris, France, on 6 March 2017.The magazine was called the “Cinema Teaser” and the outsized copy measured 2.385 m (7 ft 9.8 in) by 3.183 m (10 ft 5.3 in). The event took place at the premier showing of the film ‘KONG - Skull Island’ in France.
For a complete list of 2017 records, please visit 2017 Guinness Records in France.