KSI

KSI — Olajide Olatunji — is the most successful career-changer in YouTube history. FIFA videos, diss tracks, championship boxing, chart-topping music, a drinks empire, reality TV judging: every time the internet decided what KSI was, he became something else.

It started with FIFA. Loud, funny, relentlessly upload-driven gaming videos made him one of the UK's first YouTube superstars, and the Sidemen — the creator collective he co-founded in 2013 — became a British institution: football challenges, comedy formats, and eventually a Netflix documentary chronicling the rise from bedrooms to mainstream. In 2026, after 13 years, KSI announced his departure from the group, closing the defining chapter of UK YouTube.

The pivots are the legend. Diss tracks aimed at fellow YouTubers revealed a genuine rapper — "Lamborghini," "Keep Up," and later "Thick of It" became real chart hits. Then came boxing: the 2018 grudge match with Logan Paul in Manchester (a draw), the 2019 professional rematch in LA (a KSI win), and subsequent bouts including Tommy Fury — crossover boxing's biggest events, with KSI as both fighter and promoter through Misfits Boxing.

The business moves matched the ambition. Prime Hydration, co-founded with Logan Paul, became a global drinks phenomenon. A judging seat on Britain's Got Talent put him on mainstream Saturday-night TV. Few creators have ever converted internet fame into this many real-world industries.

Why people watch: KSI is proof that a YouTuber can be a mogul without losing the chaos that made them fun. The uploads still feel like events because he treats them that way. Fans of Logan Paul's own reinvention or MrBeast's scale will recognize the same playbook — think bigger than the platform, then execute.

What's next is the most interesting question in UK YouTube. Post-Sidemen, KSI's empire — music, boxing promotion, Prime, television — runs on its own momentum, and the farewell video made clear the decision was about focus, not fallout. Thirteen years in a collective most people couldn't survive thirteen months in. Previously covers KSI because whatever the next era is, it'll be loud, ambitious, and impossible to ignore.

2026 was the year the reinventions came due. In January, appearing on The Ranveer Show, KSI announced his retirement from boxing: “When it comes to boxing, I'm done,” he said — admitting he'd turned down a $30 million offer to finally fight Jake Paul because the negotiations had become excuse after excuse, and because he'd never loved the training. The October 2023 majority-decision loss to Tommy Fury had been the turning point: a broken hand, a body that had had enough, a heart that wasn't in it. It closed a chapter that began with the Joe Weller fight in 2018, ran through the Logan Paul draw and the split-decision rematch win in 2019, and peaked with two knockouts in one night in August 2022. He'd also been ousted from Misfits Boxing — the promotion he co-founded — at the end of 2025, replaced as the face of the company by Andrew Tate, a split he denounced publicly.

Then came the bigger shock. On May 31, 2026, KSI posted “I'm Leaving The Sidemen,” a thirteen-minute video announcing his departure from the collective he'd co-founded thirteen years earlier. “This is honestly the hardest video I've ever had to make in my life,” he said. The group posted a statement on X confirming the exit had been a complete surprise to them too, and wishing him well. The timing told its own story: the Netflix series Outside — the wilderness spin-off of the Sidemen's Inside reality format, a concept KSI himself had originated — had been filmed in May 2026, just before the announcement, making it his final project with the group. It dropped on Netflix in September 2026 with KSI in it, a farewell he hadn't known he was filming.

What replaced those chapters was already in motion. KSI joined the judging panel of Britain's Got Talent for its 2026 series, completing a journey from bedroom FIFA videos to Saturday-night mainstream television. He took a management role in the Baller League, the creator-driven indoor football competition. The music catalog kept its own momentum: Dissimulation hit No. 2 in the UK, All Over The Place followed, Caught in Two Minds marked a more reflective turn, and “Thick of It” became a genuine chart hit. His personal channel sits past 18 million subscribers with a YouTube Diamond Award — numbers that belong to institutions, not individuals.

The throughline through all of it is Prime. The hydration brand he co-founded with Logan Paul — his former boxing rival — became a genuine drinks-industry phenomenon, a billion-dollar-scale business that proved KSI's pivots weren't stunts but strategy. FIFA to rap to boxing to music to drinks to television: every era looked like a gamble and every one paid. Post-Sidemen, the empire runs on its own momentum, and the farewell video's closing line — that the decision was about focus and sanity, not fallout — reads as the thesis of the whole career. KSI doesn't follow the internet's attention. He moves first and lets it catch up.