|Born||25 January 1995|
Rijswijk, the Netherlands
|Residence||Arnhem, the Netherlands|
|Height||1.84 m (6 ft 0 in)|
|Highest ranking||25 (28 June 2018)|
|Current ranking||35 (18 February 2020)|
He was selected to join the national team in 2008, and made a debut in international senior tournament in 2012. Caljouw competed at the 2013 European Junior Championships in Ankara, Turkey, winning a silver medal in the boys' singles event, and also a bronze medal in the mixed team event. He was selected by Badminton Europe to join the Player Development Plan "Future Stars". Caljouw won the men's singles National Championships title in 2017, beating defending champion Erik Meijs in the semi-finals and first seeded Nick Fransman in the final. He defended the title in 2018, after beating Fransman,  and also in 2019 beating youngster Joran Kweekel in the final.
He reached the semi-finals of the Dutch Open and the Scottish Open both twice in 2017 & 2018. In 2017, he also reached the semi-final of the Bitburger Open in Germany. In 2018 he won his first big title the Orleans Masters then a BWF Tour 100 event, after defending the title he won the previous year when the event was still an International Challenge event. In 2018, he also reached the final of the US Open, an BWF Tour 300 event. In 2019 he won the Austrian Open.
European Junior ChampionshipsEdit
|2013||ASKI Sport Hall, Ankara, Turkey||Fabian Roth||17–21, 14–21||Silver|
BWF World Tour (1 title, 1 runner-up)Edit
The BWF World Tour, announced on 19 March 2017 and implemented in 2018, is a series of elite badminton tournaments, sanctioned by Badminton World Federation (BWF). The BWF World Tour are divided into six levels, namely World Tour Finals, Super 1000, Super 750, Super 500, Super 300 (part of the HSBC World Tour), and the BWF Tour Super 100.
|2018||U.S. Open||Super 300||Lee Dong-keun||21–14, 17–21, 16–21||Runner-up|
|2018||Orleans Masters||Super 100||Rasmus Gemke||10–21, 21–18, 21–8||Winner|
BWF International Challenge/Series (3 titles, 1 runner-up)Edit
|2019||Kharkiv International||Ade Resky Dwicahyo||21–15, 21–10||Winner|
|2019||Austrian Open||Li Shifeng||8–21, 23–21, 21–9||Winner|
|2017||Orleans International||Lucas Corvée||21–6, 18–21, 21–11||Winner|
|2013||Norwegian International||Kasper Lehikoinen||17–21, 16–21||Runner-up|
- "Spelers: Mark Caljouw". badmintonline.nl (in Dutch). badmintonline.nl. Retrieved 16 August 2016.
- "Players: Mark Caljouw". bwfbadminton.com. Badminton World Federation. Retrieved 16 August 2016.
- "Juniorski šampionat Evrope 2013. godine - Ankara, 26.03. - 31.03.2013. godine". badminton-bl.com. Badminton Club Banjaluka. Retrieved 1 April 2018.
- ""Future stars" selected". Badminton Europe. Retrieved 1 April 2018.
- "Caljouw en Mahulette winnen NK badminton" (in Dutch). Nieuws.nl. Retrieved 1 April 2018.
- "BWF Launches New Events Structure". Badminton World Federation. 29 November 2017.
- "Action-Packed Season Ahead!". Badminton World Federation. 15 January 2018.