When JJ Olatunji started recording himself playing computer games from his bedroom, he could never have predicted he would have a media empire worth millions in just a few years.
The 27-year-old YouTube sensation, known around the world as KSI, built up a global following by uploading gaming videos while he was still at school.
KSI, who has tattooed the words his nickname stands for on his body, Knowledge, Strength, Integrity, has made a fortune by turning mouse clicks into cash and now has more than a staggering 30million subscribers across his various channels.
After disappointing exam results, the teenager made the bold move to leave education altogether and focus on building a career recording entertaining videos for the masses.
The hard-working YouTube star, who is appearing on tonight's The Great Celebrity Bake Off, has now expanded his impressive portfolio into creating chart-topping music and fighting in boxing pay-per-views.
Here is a look at how KSI made his millions and his incredible net worth.
YouTube goldmine
KSI has confessed his parents were initially disappointed with his decision not to go to university, having put their savings into sending him to private school in the hope he would become a lawyer or doctor.
After underperforming in his A levels he did an international baccalaureate diploma for 18 months, but the turning point came when he found out his YouTube earnings meant he was making more money than one of his college lecturers.
"I remember I asked a teacher, this is how I made this month, it was about £1,500 and I remember him telling me 'that's more than I make'," he told Louis Theroux on his Grounded podcast in June last year.
"I looked at it and I thought, that's it, YouTube is the one, it is the goldmine. I need to push and push because I know I can become something and make my parents proud."
KSI struggled "for a couple of years" with the anguish his parents felt about his decision not to go to university and didn't want to let them down.
He added: "But eventually I decided, 'you know what, screw it. I'm going to make them proud through the whole YouTube.'
"As long as I can get rid of all their debts and make their lives comfortable, that's all that matters."
His videos initially concentrated on himself playing the popular console game FIFA but he has now ventured into a variety of content.
He is also part of The Sidemen, a group of seven British YouTube stars who produce their own videos together as well as releasing books and a clothing line.
Most of KSI's earnings still come from YouTube, where he has racked up more than six billion views.
YouTube do not release the earnings of its users but some of his videos generate £250,000 in advertising fees.
Property empire
KSI had been investing his YouTube millions into building an estimated £10million property empire.
Last June, the Sunday Mirror discovered that KSI now has more than 12 high-end flats and homes.
A source said: "He’s worth a packet. It’s a real success story."
In 2019 his property development firm Kilimanjaro Your Mum Ltd spent £1.5million on new addresses to add to the £8million of housing stock he’s bought in the past few years.
And his firm paid cash, so there are no mortgage interest charges.
Accounts show the firm also has £164,000 in cash in its coffers from income generated. Another of his companies – The Throne Holdings – has cash and assets of £2.9million.
Meanwhile a production company called Ksiolajidebt Ltd has cash reserves of almost £1million.
Boxing champion
KSI switched his attention to boxing and took on fellow British YouTube star Joe Weller at the Copper Box Arena early in 2017.
The fight was streamed for free you on YouTube and so it is not known how much KSI made, but his TKO win in the third round put him on the boxing map and set up a grudge match with American rival Logan Paul.
The pair were held to a draw in the Manchester Arena in August 2019 in what was described as "the biggest amateur boxing match in history".
While 21,000 watched it live in Manchester, it was streamed on YouTube for the price of £7.50 and has been viewed more than 75million times since.
Although official details were never revealed, one estimate claimed the first fight made £150million, including lucrative sponsorship deals they signed.
When quizzed on speculation he had made £40m, KSI said: "It’s definitely not right, that’s ridiculous that amount.
"I mean obviously it’s a high amount, but it’s nowhere near £40m."
The YouTube stars met again for a rematch in November 2019 - with KSI coming out on top in a split decision.
He pocketed £700,000 as stipulated in their contract with the California State Athletic Commission, but his final earnings with a cut of the pay-per-view fees and gate receipts are expected to be far higher.
Chart-topping music
Having started off writing rap music in his bedroom, KSI became an actual artist and released debut single 'Lamborghini' in 2015 and got into the UK top 40.
Since then he has gone on to release four EPs, 18 singles, and 28 music videos - making money when they are purchased or streamed online.
KSI has produced music with many big names including Craig David, Anne-Marie and Rick Ross, while latest single 'Patience' with Yungblud and Polo G has reached number 3 in the UK charts.
In February, KSI announced he was launching his own record label 'The Online Takeover' and has signed his first artist, British-American singer Aiyana-Lee, which means he will be raking in even more money.
Unfortunately he had to cancel his your last year due to Covid-19 but he is hoping to be back in arenas and at festivals later this year.
£16million net worth
KSI is estimated to have a staggering net worth of £16million.
And it seems that figure won't be slowing down anytime soon as he continues to have success on YouTube and with his music career.
His main channel which is now completely devoted to his music videos has more than 22million subscribers.
While his second YouTube channel titled JJ Olatunji, which features more of the comedy and gameplay that he's known for, has an impressive 12.3million subs.
KSI likes to give back and has supported a number of charitable causes over the years - most recently giving £10,000 to BBC Radio 1's 'Lol-a-thon' for Comic Relief.
In June 2019 he uploaded a video titled "Ending It All" from which all ad-revenue was donated to various suicide-prevention charities.
When asked by Louis Theroux if reports that he is worth around £16 million were true last year, KSI said: "I guess, I am wealthy yes.
"I've been doing YouTube for 10-plus years, I had a lot of money coming from different angles, in different areas so it makes sense for me to be worth eight figures yeah."