|Full name||Karl-Johan Johnsson|
|Date of birth||28 January 1990|
|Place of birth||Ränneslöv, Sweden|
|Height||1.87 m (6 ft 1 1⁄2 in)|
|* Senior club appearances and goals counted for the domestic league only and correct as of 10 July 2014 (UTC).
† Appearances (Goals).
In 2005, at the age of 15, Johnsson moved to Halmstads BK. Johnsson began his career in Ränneslövs GIF. When goalkeeper Marcus Sahlman was loaned to Trelleborgs FF Johnsson was picked up as third choice goalkeeper on the senior team and he made his game debut on 24 August 2008 against Djurgårdens IF when Magnus Bahne was forced to leave the field during halftime. On 20 November 2008 it was reported that Johansson would go to Manchester, England, for a week and join Manchester City during training. As Conny Johansson retired and Marcus Sahlman left for Tromsø IL, Karl-Johan was made second choice goalkeeper for the 2009 season.
During the 2010 season Johnsson became second choice behind Robin Malmqvist. The 2011 season became turbulent, at first Halmstads BK appointed Josep Clotet Ruiz as new manager of the club, this saw changes among the goalkeepers as Malmqvist was loaned out to Tromsø IL in Norway and Spanish keeper Nauzet Pérez was brought in as first choice, however poor performance and problems with adapting to the Swedish lifestyle saw Pérez depart the club before half the season was played, with his departure Johnsson was appointed first choice as goalkeeper at the club.
Karl-Johan Johnsson represented Sweden at U19 level before moving up to the Swedish U21 team and debuting against the Slovakian U21 team in 2009. Over time Johnsson was able work himself into becoming the first choice goalkeeper in the U21 team.
Despite Halmstads BK's poor performance in Allsvenskan 2011 and their relegation, Karl-Johan Johnsson was called up to the Swedens national team for the 2012 January tour against Qatar U23 and Bahrain, missing out on the game against Bahrain, he then came on as a substitute in halft time against Qatar, making his senior team debut.
- "Officiellt: Karl-Johan Johnsson klar för NEC Nijmegen" (in Swedish). Fotbolltransfers. Retrieved 4 April 2013.
- "Djurgården vann över Halmstads BK" (in Swedish). Hallandsposten.se. 24 August 2008. Retrieved 1 July 2009.
- "Kalle tränar med Manchester City" (in Swedish). HBK.se. 19 November 2008. Retrieved 19 May 2009.
- "Keeper training with City". Skysports.com. 19 November 2008. Retrieved 30 June 2009.
- "Förändringar i truppen" (in Swedish). hbk.se. 29 May 2011. Retrieved 11 March 2012.
- "Tuff press på ung HBK-keeper: "Kan bli problem"" (in Swedish). fotbolldirekt.se. 30 May 2011. Retrieved 11 March 2012.
- "Kalle lämnar HBK efter säsongen" (in Swedish). hbk.se. 5 November 2012. Retrieved 5 November 2012.
- "N.E.C. legt talentvolle keeper Kalle Johnsson vast" (in dutch). nec-nijmegen.nl. 5 November 2012. Retrieved 12 November 2012.
- "Herr: Nio U21-spelare med till Qatar" (in Swedish). svenskfotboll.se. 14 December 2011. Retrieved 11 March 2012.
- "Storseger mot Qatar" (in Swedish). svenskfotboll.se. 23 January 2012. Retrieved 11 March 2012.