John, 20, who has made only one first-team appearance for Cardiff this season, will initially stay with Chesterfield until March 15
The Wales international will be eligible to play in five Sky Bet League One matches for Danny Wilson's side
John, who progressed through Cardiff's academy, has made 36 appearances for the Welsh club in total and featured nine times for Barnsley during a loan spell at Oakwell at the end of last season
Source : PA
Source: PA