According to Forbes there are 2,153 billionaires in the world, with a combined net worth of around $8.7 trillion (£6.6tr). Despite sounding like an astonishing number, there are actually 55 fewer people on the list than last year, and a record 46% are, in relative terms, poorer than 12 months ago. Nonetheless there are a number of fresh-faced entrepreneurs under 40 who earn the accolade of being the youngest self-made billionaires on the planet. Here's who they are, from oldest to youngest.

Markus ‘Notch’ Persson, 39, the billionaire creator of Minecraft, sold his independent gaming company Mojang and the franchise to Microsoft in a $2.5 billion (£1.9bn) cash deal. He joins the world’s super-rich with a net worth of $1.6 billion (£1.2bn).

Mike Cannon-Brookes, 39, and business partner Scott Farquhar studied together and co-founded a bookmark management tool which they sold to set up software company Atlassian. The company acquired OpsGenie, an incident management service, for $295 million (£256m) at the end of 2018 and Forbes estimates Cannon-Brookes' net worth at $6.9 billion (£5.3bn).

Cannon-Brookes' business partner Scott Farquhar is also just 39. With A-list customers such as BMW, Citigroup, Cisco, NASA and Facebook, software company Atlassian has catapulted them both onto the billionaire list. Forbes estimates Farquhar's net worth at $6.9 billion (£5.3bn) too.

Sean Parker, 39, is the co-founder of online music service Napster, but much of his fortune comes from his brief turn as Facebook's president when he was just 24. He also founded Brigade Media, a start-up that allows people to share their opinions and debate them, and his net worth is estimated at $2.7 billion (£2.1bn).

Zhang Bangxin, 38, was tutoring and working seven part-time jobs alongside studying for a PhD when he co-founded US-listed education services TAL Education, where he has also held the role of chairman and CEO since the company’s creation. In China, TAL is one of the most important private education networks, with at least 301 schools. His net worth is estimated at $6.2 billion (£4.7bn).

Chinese entrepreneur Frank Wang, 38, who founded the world's most successful drone company DJI in 2006, owns 40% of the firm, which has reported more than $2 billion (£1.5bn) in sales. His net worth is said to be $5.4 billion (£4.1bn).

While a student, Fahed Hariri – the youngest son of assassinated Lebanese Prime Minister Rafic Hariri – ran an interior design studio and sold furniture to clients in Saudi Arabia. Now 38, with a net worth of $1.3 billion (£995m), he develops residential buildings in Beirut and credits his late father for his love of real estate development.

In 2007 Brian Chesky, now 37, and his housemate Joe Gebbia couldn’t afford to pay their rent so they teamed up with engineering whiz Nathan Blecharczyk and created Airbnb. Now Chesky’s net worth is $3.7 billion (£2.8bn)

Airbnb co-founder Joe Gebbia, 37, has a net worth of $3.7 billion (£2.8bn), ranking him equal to Brian Chesky – both own 15% stakes in the company which has changed the way we travel. More than 300 million people have used the site, which operates in over 190 countries.

In 2007, former Amazon executive Sachin Bansal, 37, co-founded Flipkart, an online seller of books, with friend Binny Bansal (no relation). Last year, Walmart purchased a 77% stake in Flipkart for a massive $16 billion (£12.2bn). So it’s no wonder Bansal’s net worth is $1.2 billion (£919m).

Binny, 37, was also a former Amazon executive before founding Flipkart with Sachin Bansal in 2007. The site is India's leading e-commerce site with more than 80 million products for sale. In January 2016, Binny took over as chief executive from Sachin, but resigned in November 2018 following allegations of serious personal misconduct. He still has a 4% stake in the company, and has a net worth of around $1 billion (£765m).

Co-founder and CEO of Pinterest, Ben Silbermann, 37, has a pretty impressive CV. He worked for Google, before designing his own apps, and then teaming up with Evan Sharp to create Pinterest in 2010. The business was valued at $12.3 billion (£9.4bn) in June 2017, and Silbermann's own net worth stands at $1.6 billion (£1.2 bn).

Evan Sharp studied studied history at the University of Chicago and architecture at Columbia, and went on to become a product designer at Facebook before he created digital pinboard Pinterest. Today he leads the creative team at Pinterest and Forbes reports his net worth is around $1 billion (£760m).

Spotting a gap in the tech market, Drew Houston, 36, co-founded Dropbox – a cloud-based file-sharing service – with Arash Ferdowsi in 2007. Dropbox went public in March 2018 and shares jumped by a massive 35% in the first day. Houston’s net worth is estimated at $2 billion (£1.5bn).

In 2008, when Daniel Ek, 36, and his much-older business partner Martin Lorentzon launched Spotify, few people would have predicted that there was money to be made from a largely free music streaming service. Yet just over a decade later, Spotify has 180 million users, the company was estimated to be worth more than $33 billion (£25.2bn) in June last year, and Ek's net worth stands at £2.2 billion (£1.7 bn).

Discover how Spotify conquered the music world

Cheng Wei, 36, is CEO of Chinese taxi-hailing service Didi Chuxing, which formed back in early 2015 when Cheng’s company Didi Dache merged with rival Kuaidi Dache. Before creating Didi Dache, he worked at e-commerce firm Alibaba. His net worth is estimated at $1.2 billion (£919m).

Armstrong, 36, rode the wave of Bitcoin's successes when Coinbase, the cryptocurrency exchange that he co-founded, made him a billionaire. Coinbase is the largest cryptocurrency exchange in the US, and was recently valued at $8 billion (£6bn) by Tiger Global, while Armstrong's net worth is $1.3 billion (£995m).

Here’s an accolade: Ryan Graves, 35, was the first employee hired at Uber, the taxi service now valued at $120 billion (£91.6bn). Graves joined Uber in 2010, when co-founder and then-CEO Travis Kalanick tweeted that he needed a product manager and Graves responded, “here’s a tip. Email me :)” In August 2017, he left the company but remains on its board of directors. His net worth currently stands at $1.6 billion (£1.2bn).

Nathan Blecharczyk, 35, made his money from Airbnb, and was the company's first engineer and co-founder. He is now the company's chief strategy officer. His net worth is estimated at $3.7 billion (£2.8bn).

The man behind photo-sharing app Instagram, Kevin Systrom, 35, has $1.4 billion (£1bn) to his name. The app had immediate success from the moment it was launched and was bought by Facebook for $1 billion (£760m) back in 2012, although Systrom continued to run it until last September when he left the company.

Dustin Moskovitz co-founded Facebook with roommate Mark Zuckerberg from their Harvard dorm. He dropped out of school after two years and joined Zuckerberg in Palo Alto to develop Facebook. His net worth is estimated at $11.2 billion (£8.6bn) by Forbes.

Boasting a net worth of $62.4 billion (£47.8bn) the Facebook co-founder is the richest self-made person under the age of 40. For a while he was also the youngest self-made billionaire ever, after joining the billionaires list at the age of just 23 in 2006. But he has since lost that title to the person at the top of our list...

Read about Zuckerberg's 15-year rise to the top

Pavel Durov, 34, is the founder of Russia's answer to Facebook: a site called Vkontakte, the country's biggest social network. After selling a 12% stake in the company for $300 million (£229m) back in 2015, Durov went on to create a messaging app called Telegram Messenger. He has a net worth of $2.7 billion (£2.1bn).

The Chairman of ByteDance, one of China's largest media content platforms, Zhang Yiming, 34, is worth an impressive $16.2 billion (£12.4bn). The company has a valuation of $75 billion (£57.3bn), with shareholders including Sequoia Capital China.

Another bitcoin billionare, Jihan Wu made his fortune through the company he founded, Bitmain Technologies. As China's largest cryptocurrency mining-chip company, Bitmain was recently valued at $12 billion (£9.2bn), while Wu's personal net worth stands at $1.5 billion (£1.1bn).

Bobby Murphy (pictured on the right) co-founded the messaging service SnapChat. The company went public in March 2017, with the stock soaring 44% on its first day of trading. Initially, after the IPO, his net worth soared to $4 billion (£3.3bn), but it has since gone down to $2.2 billion (£1.7bn).

Chris Wanstrath, 30, co-founded software development platform GitHub when he was just 20 years old. Last June, the firm was purchased by Microsoft for $7.5 billion (£5.8bn), where Wanstrath became a technical fellow. His net worth is estimated at $1.4 billion (£1bn).

Irish entrepreneur Patrick Collison founded US technology company Stripe alongside his brother John in 2010. He is CEO of the online payment company and his current net worth comes in at $2.1 billion (£1.6bn).

The other Collison brother and Stripe co-founder, John, is just 28. Their company, which employs 550 people, allows businesses and individuals to easily accept payments over the internet, and processes billions of dollars in transactions per year in 25 different countries. John's net worth is $2.1 billion (£1.6bn).

At the age of 25, Evan Spiegel earned the impressive accolade of becoming one of the youngest self-made billionaires in history. Now 28, he has an estimated $2.2 billion (£1.7bn) fortune from his SnapChat app invention with co-founder Bobby Murphy. In 2013, Facebook offered $3 billion (£2.4bn) to buy SnapChat but the pair refused. 

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At 21 Kylie Jenner is the youngest self-made billionaire on the planet ever, and the only self-made female billionaire under 40. Unlike others on our list, who made their fortunes through tech companies, she has her Kylie Cosmetics range to thank for her fortune, although she got more than a little break from her role in reality TV smash Keeping Up with the Kardashians. After starting selling $29 (£22) lip kits three years ago, she entered into a distribution deal with Ulta last year and sold $55 million (£42m) of cosmetics in just six weeks. Her net worth stands at $1 billion (£776m) and the company, which she has a 100% stake in, is worth $900 million (£687m).

Now meet the stars who are even richer than their parents