He was born during the reign of his maternal grandfather, King Frederik IX, and became Crown Prince of Denmark following his mother's accession in 1972.

Frederik met Australian marketing consultant Mary Donaldson while attending the 2000 Summer Olympics in Sydney.

[16] As part of his education, he spent the 1992–1993 academic year at Harvard University, where he studied political science under the name Frederik Henriksen.

[18] Queen Margrethe II announced her abdication during her annual live broadcast New Year's Eve address on 31 December 2023.

Frederik succeeded her as King of Denmark on 14 January 2024, after Margrethe formally signed an instrument of abdication during a meeting of the Council of State.

[26] After succeeding to the throne, he was proclaimed king from the balcony of Christiansborg Palace by Prime Minister Mette Frederiksen as has been the custom for Danish monarchs since the introduction of the constitutional monarchy in 1849.

[29] On 31 January 2024, Frederik visited Poland and was received by its president Andrzej Duda, in his first overseas trip as monarch.

Danish monarchs traditionally travel first to another Scandinavian country, but Frederik had planned the trip prior to Margrethe's abdication.

[35] In January 2025, when U.S president elect Donald Trump renewed talks about the intended U.S purchase of Greenland, the King held a speech promoting unity and collaboration within the Kingdom of Denmark.

[50][51][52] The prince was one of the authors of the Kongelig Polartokt (Polar Cruise Royal), about the challenges of climate, published in 2009 with a preface written by Kofi Annan.

[53][54][55] In 2010, he wrote the foreword to the highschool textbook Naturen og klimaændringerne i Nordøstgrønland (Nature and climate change in Northeast Greenland).

[56] He supports scientific research projects, as a patron, as expeditionary, with regular attendance at events and through his foundation, Kronprins Frederiks Fond.

[70] At the 2003 Dragon European Championship, where 51 boats participated, the Prince and his crew had been leading after four out of six races; they finished in fourth place.

[79] In October 2016, Frederik had to cancel his appearance at the royal reception for the Danish Olympic and Paralympic athletes after he fractured his spine while jumping on a trampoline with his eldest son.

[80] Frederik also took part in the relay event during the 2019 IAAF World Cross Country Championships in Aarhus in March 2019.

[89] Also in 2016, Frederik completed the 160 km (99 mi) Arctic Circle Race [de; fr; sv] in Sisimiut, Greenland.

[93] The Crown Prince was given special observer status in National Olympic Committee and Sports Confederation of Denmark, as a way to allow him to work, without having political power.

[94] Frederik announced that his point of focus and reason for joining the International Olympic Committee is to promote an active lifestyle among youth.

Prince Frederik was part of the polar expedition as a film photographer, whose job was to ensure an optimal coverage of this event.

[110][111] The purpose of the foundation is to provide financial assistance to students of social policy and sciences, for one year's study at Harvard.

[112] It also provides financial support for scientific expeditions, particularly to foreign parts of the world, such as Greenland and the Faroe Islands, and sports purposes, including those with a particularly social aspect.