Hanyu made the announcement at a hastily arranged press conference in Tokyo, his first since the Beijing 2022 Olympic Winter Games.
And there were no tears, just smiles, as one of Japan's most popular athletes called time on an unrivalled competitive career in the sport.
"I have decided to go into professional figure skating", Hanyu said, decked out in a sharp navy suit and appearing at times nervous.
"I'm not sad at all. There's no sadness. And I want to keep working.
"But I'm no longer confined to the realm of competitions anymore. I think I can take figure skating to different places in different ways now".
Hanyu said he made his final decision as he was treating the right-ankle sprain he suffered ahead of the free program in Beijing.
"I can say for sure that I won't miss the tension of a competition", he said. "But I hope to work as hard as ever so people will want to keep supporting Hanyu as they know him.
"After the Beijing Olympics when I got home, I couldn't skate because of the pain in the ankle. I thought about all kinds of things then but I felt that I don't need to be on this stage forever."
Olympics is "proof that I lived"
The Sendai, Miyagi Prefecture, native goes out widely recognised as the greatest male figure skater of all-time.
The 27-year-old put an end to a career that began when he was 4 years old, and ended with a fourth-place finish in Beijing after a historic attempt at the quadruple Axel.
Hanyu had not addressed his future since Beijing. Last month, he completed a four-stop, month-long ice show tour through Japan during which he did not do media.
But with the new season approaching, a decision either way had to be announced soon - and that day was Tuesday.
Over his career, Hanyu won just about everything there is to win on the ice.
On top of his gold medals, he leaves with two world championships, four Grand Prix Final wins and six national championships including last year's, which he won to punch his ticket to Beijing.
His highest score came at Skate Canada in 2019, when he produced 322.59 points. His best in the short program is a 111.82, a 212.99 in the free skate.
In 2018 following his second Olympic triumph in PyeongChang - he became the first man in 66 years to repeat as singles champion - Hanyu received the People's Honor Award - the highest honour awarded to a civilian in Japan.
Yet of all his achievements, the Games hold a special place in his heart.
"It goes without saying that the Olympics to me, after winning back-to-back, has put me where I am now", he said. "It is a place where I was able to prove that I dreamed, that I put in the effort.
"It gave me proof that I lived".
Still after the quad Axel
As for his future plans, Hanyu did not offer details other than that he is heading to the ice show circuit.
“There’s a lot of things I’m thinking, discussing and planning at the moment but I can’t go into details yet", he said.
“I want to put on a show that’s fitting of the times and also one that will be attractive to someone who’s never watched figure skating before".
But he did say his chase for the quadruple Axel is still on - it just won't be done at competitions.
"I want to keep challenging. I want to land the quadruple Axel in front of everybody", .
"I can still pursue it. It just won’t be on a competitive stage".