The prince looks incredibly handsome in the snap, with his "piercing" blue eyes capturing the attention of many.
Hundreds of fans wished Frederik a happy birthday, with many also pointing out how handsome he looked.
One fan wrote, "A magnificent future leader of Denmark. And a hunk." While another added, "So handsome, happy birthday Frederick."
Someone else wrote, "Like a fine wine, he just keeps getting better," with another adding, "52 looks great on you!"
"His eyes are piercing," another fan wrote. Someone else commented, "Nice blue eyes."
"What an absolutely amazing picture," another stunned fan wrote.
One fan shared a lengthy message, which, translated from Danish, reads, "I have to say something; he really looks like a happy man who enjoys his role, duties and job. He has then found his shelf here in life, after personal victories and probably most after finding a loving wife in Crown Princess Mary and having children, a dog and her own little safe home base. A safe haven.
"What a change from uncertain and with courage radiance to his strong radiance now! For the past 15 years we have just seen an increasingly confident, proud and happy man. Both as crown prince, husband, father, and future king of Denmark. His eyes are beaming. The royal house is rich yes, but love – that is what wealth is. Nice he found it! And himself!"
Clearly the Prince has a lot of fans.
A very relatable Prince
Frederik recently shared a hilarious quarantine photo of himself the day hairdressers were finally able to open in Denmark.
Prince Fred like many others Danes dutifully went to get a trim, sharing a hilarious pair of side-by-side snaps showing his hair before and after the ban was lifted.
Needless to say in the ‘before’, his hair looking a little less coiffed than it usually would in his royal public appearances.
“I'm probably not the only one who has been to a hairdresser today,” he jokes in his caption, translated from Danish.
“Fortunately, it is now possible for hairdressers and other smaller companies and stores to stay open on top of a long shutdown.”
Taking a more serious tone Frederick went on to thank Denmark for their efforts during the lockdown.
“I want to thank everyone for being so readily prepared and for helping keep the wheels going for a period that requires a lot of us all,” he wrote.
Royal watchers flooded the post with appreciation for the very human side of the Prince on display.
“We have by far the coolest Crown Prince in the world,” one woman wrote.
“I look so forward to him being our king, so brilliant,” another agreed.
“Thank you [for] showing us that you are [one] of us,” another wrote.
More than one were quite the fans of the initial look, some finding the unkempt curls quite a roguish look for the Danish royal.
“Ok, I’m in love with the curls,” one woman admitted.
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