Millionaire Fast Track: 27 CEOs Under 27 These 27 young entrepreneurs prove that age is just a number.

After earning her master's degree, Mathilde Collin found herself glued to a desk job she didn't enjoy. Instead of accepting her circumstances, she decided to do something about it and launched her own company at the age of 22.

Many young people accept their current situation, thinking they need to be older before they make more money. This is false.

Here are 27 young CEOs who have all achieved extreme success before their 27th birthday. They joined me on my podcast, The Top Entrepreneurs, to share their revenue numbers, customer counts and lessons learned.

1. Mathilde Collin, 26 years old, CEO and co-founder of FrontApp

The company Collin launched after quitting her desk job was FrontApp. The app is an email inbox with features that are specifically meant for teams. The company did $1 million in 2015 revenue and now has 1,210 customers and $242,000 in monthly recurring revenue.

Collin isn't done yet. She's raised $13 million and is growing the company at 10 percent month over month.

What she wishes her 20-year-old self knew: You can be totally happy at "work."

Click play below to listen to Collin's war story:

2. Iddo Gino, 19 years old, CEO and co-founder of RapidAPI

Gino founded his company in Israel at the age of 16. RapidAPI initially started as an open-source project that allowed developers to easily find and use APIs online. He now makes money by charging a processing fee ranging from 10 to 25 percent.

Gino now has 20 people on his team and has raised $3.5 million to date.

Related: This Entrepreneur Skipped College and Made $1,037,100 in 5 Months

3. Nathan Barry, 26 years old, CEO of ConvertKit

Barry came up with the idea of ConvertKit after he grew tired of the agency work he was doing. The team of 20 helps over 10,000 paying customers manage their email lists. The company is self-funded and did $300,000 in 2015 revenue. As of mid 2016, the company does $480,000 in revenue per month, all from its headquarters in Idaho and Nashville.

It's even more impressive that Berry's doing this while raising two young kids.

What he wishes his 20 year old self knew: He would have doubled down on his company faster.

4. Nick Kullin, 26 years old, CEO of Second Flight Consultancy

Kullin started his first business at the young age of 13 by connecting people to new artists. From that business, he made over $20,000. After high school, he took on lots of different jobs and realized soon that he had a burning desire to be an entrepreneur again, even though he had a job that paid him $120,000.

His company Second Flight Consultancy is a marketing academy that offers ambitious entrepreneurs online coaching lessons. The company did $12,000 in its first year, $175,000 in 2015 and $1.2 million in 2016.

What he wishes his 20 year old self knew: Just start.

5. Sahil Arora, 18 years old, CEO of Tabverts

Arora launched Tabverts to help put advertising in the back seats of taxis in India. His many customers include SnapDeals.

As of February 2017, the company passed $70,000 in monthly recurring revenue and has raised $500,000 from an Indian venture capitalist. Today, his company is valued at over $2 million.

What he wishes he knew when he was 20: He's not 20 yet!

Related: This Entrepreneur Teaches Millennials How to Quit Their Jobs and Start Their Lives

6. Laura Behrens Wu, 25 years old, co-founder and CEO of Shippo

Behrens Wu started her business Shippo at the age of 21. The idea was born after she faced shipping obstacles with her previous ecommerce product. Shippo makes money by charging customers a "pay as you go" fee and is currently shipping over 1 million packages per month for over 10,000 unique customers.

With $9 million in funding, Behrens Wu's San Francisco based team is 28 strong.

What she wishes her 20 year old self knew: Trust that things will turn out right.

Click play to learn how Behrens Wu got her first 100 customers:

7. Brian Wong, 25 years old, founder and CEO of Kiip

After being laid off, Wong found two co-founders and landed $300,000 in seed capital to set up Kiip, an advertising tool that rewards its users for achievements inside of applications.

His co-founders decided to move onm but Wong didn't lose focus with the company passing $20 million in 2016 revenue. $11 million worth of advertising spend has been processed using Kiip and Wong has raised a total of $32 million for the venture.

What he wishes he knew when he was 20: Stop taking everything so serious.

8. Wyatt Jozwowski, 21 years old, CEO and co-founder of Demio

Jozwowski invested $500,000 to re-invent webinars with Demio, a smart webinar platform. He made his original money through his company Drip Apps, where 470 people paid $47 per month to take digital courses about digital marketing. Drip Apps did just shy of $1 million in 2015 revenue. He's now doubling down and going all in on Demio.

What he wishes his 20 year old self knew: Persistency wins.

9. Tommy Gibbons, 25 years old, partner at Piper

Gibbons and his partners created Piper to teach young children how to build their first computer. Following a $280,000 Kickstarter campaign, the product was an instant hit, quickly passing 4,000 units sold and nearly $1.2 million in revenue.

Whlie the product costs $299 for consumers to purchase, it costs Piper $100 to produce, leading to a 70 percent gross margin. The company has raised $2.3 million to date.

Prior to Piper, Gibbons was working for Goldman Sachs and Fundera.

10. Alex Saidani, 21 years old, founder and CEO of Indemand

Saidani got off to an early start, learning to code at the age of 11 and launching his first business at 13.

His company Indemand provides businesses with online ordering software and an hourly delivery network. He's managed to find success even with a small team of three that has raised $125,000 with 25 paying customers.

What he wishes he knew when he was 20: Don't waste time pursuing non-value creating people

11. Shashank Murali, 23 years old, co-founder and CEO of TapChief

Murali already has one win under his belt, selling his first company at 20 years old. Using that money, he founded TapChief, a platform that connects experts with students. To date, 5,000 experts are listed on TapChief, and 1,000 students have paid to use the service. Murali makes money by charging experts $4 to get listed, and then takes a 20 percent cut of payments from students to experts.

The company has raised $150,000 with a team of 10 and has delivered over 75,000 minutes of experts teaching students.

What he wishes he knew when he was 20: Be more persistent.

Related: 5 Lessons From a Teenager Who Founded Her Own Record Label

12. Andrew Myers, 23 years old, CEO of Ripple Recruiting

Myers grew up in Denver and decided to leave Yale before the start of his senior year to launch his company, Ripple Recruiting. The company connects thousands of Ivy League resumes with employers who pay Ripple Recruiting an average fee of $300 per month.

The team of 12 has raised $700,000 and has helped 20,000 students get hired.

13. Douglas Lusted, 24 years old, CEO and co-founder of Linkett

In 2013, 20-year-old Lusted founded his company, Linkett, and did $100,000 in first -year revenue. The company specializes in out-of-home advertising: Google AdSense for physical billboards.

Based in Canada, Lusted has raised $125,000 and quickly passed $250,000 in annual revenue.

What he wishes his 20 year old self knew: To keep on moving. Momentum is king!

14. Vu Hoang Anh, 23 years old, founder and CEO of Avocode

Anh founded Avocode, a tool that allows front-end designers to connect with back-end developers to make it easier for designers to pass off designs to development teams. He has grown the service to over 2,800 customers paying, on average, $18 per month.

The company has raised $125,000 and is growing 15 percent month-to-month with revenues in mid-2016 of $50,000 per month.

What he wishes his 20 year old self knew: Measure everything and focus on retention.

15. Looi Qin En, 23 years old, COO and CMO of Glints

Before Looi turned 20, he had published 20 behavioral science research papers in international journals. He used this expertise to launch Glints, a platform for graduates to find jobs they love.

In his first year, 2013, total revenue was just $7,000. He went on to raise a $500,000 seed round of funding in 2014, and in 2015 he passed $500,000 in revenue by placing over 2,500 graduates into new jobs. The tool is free for students. Glint makes money by charging employers an average of $1,000 to meet potential new hires.

Looi did all of this despite the fact that his parents prefered he do something more traditional with his life.

16. Tatyana Mitkova, 24 years old, CEO and founder of Claim Compass

Mitkova has had many frustrating experiences with airlines. With her legal background, she decided to do something about it by launching Claim Compass. The business helps airline passengers submit a claim online for delayed, cancelled or overbooked flights. Claim Compass has helped 1,000 airline passengers get $420 each back from airlines for lost items and cancelled tickets.

The company makes money by keeping 25 percent of whatever they get airlines to pay you back. With $420,000 paid back to fliers, the company has made over $100,000 despite being just 18 months old.

What she wishes she knew when she was 20: Life gets more and more interesting with every decision you make.

Related: 4 Kids Who Are Disrupting the Fashion Industry

17. Slater Victoroff, 24 years old, CEO and founder of Indico Data Solutions

Indico is a text and image analytics provider that helps financial firms process data faster. Victoroff has grown his Boston team to 10 people and has raised $4.5 million. The company did $500,000 in 2015 revenue and passed $1 million in 2016.

What he wishes he knew when he was 20: That he would love programming so much.

18. Dominik Vacikar, 24 years old, associate at Hummingbird VC

Vacikar was the co-founder of a bootstrapped lead generation company called Spaceship after stints driving growth at other startups. He has since become one of the world's youngest venture capitalists by joining Europe-based Hummingbird VC. He's focused on building a tech platform at the VC firm that will help surface fundable startups.

What he wishes he knew when he was 20: You should always feel stupid about things you've done in the past.

19. Brandon Foo, 24 years old, co-founder and CEO of Polymail

Foo co-founded Bruin Entrepreneur Organization at UCLA and CTRL LA Collective, a co-working space in LA. His latest venture is Polymail, which helps businesses be more productive in their inboxes. Polymail has grown to over 20,000 daily active users (DAU), which Foo was able to use to raise $1 million in seed capital.

Next up? Monetization.

What he wishes he knew when he was 20: Focus less on school.

20. Danavir Sarria, 22 years old, founder of CopyMonk

After having gained considerable experience as a freelance copywriter, Sarria wasn't interested in working with clients anymore and decided to start his own business. With CopyMonk, he made his dream come true: Teaching people how they can increase their sales by creating effective and professional copy. At the young age of 22, Sarria is on his way to establish himself as an expert in copywriting. He did 40 sales the day he launched the business, putting $6,000 into his bank account.

What he wishes he knew when he was 20: Focus on efforts, not passions.

21. Laurence Girard, 25 years old, CEO and founder of Fruit Street

Fruit Street helps doctors legally (in compliance with HIPAA) do consultations with their patients via video chat. The company is a public-benefit corporation that has 180 shareholders. Girard created the idea after studying pre-med at Harvard University Extension School and working as a volunteer in an emergency room unit in Huntington Hospital in Long Island, N.Y., where he witnessed the issue firsthand.

So far 180 customers pay for the service, and Girard has raised $6 million to continue driving growth. His team of 20 is based in New York and broke $100,000 in revenue in 2016.

What he wishes he knew when he was 20: Put more significance on your first hires and team building.

Related: 25 Kids Who Made Millions Before Graduating From High School

22. Hamza Amir, 25 years old, CEO of Blurbiz

When working as a marketing guru for big brands, such as Coca-Cola and Disney, Amir spotted a gap in mobile content creation. To solve the problem, he created BlurBiz, which helps brands create mobile video ads. The company got early traction by helping big brands create SnapChat stories that got over 20,000 views each.

Despite success, Amir only pays himself $2,500 per month and focuses the rest on the business. The company has raised $2.4 million as of the end of 2016 and reached revenues of $60,000 per month.

23. Mike Wilner, 25 years old, co-founder and CEO of Compass

Wilner created Compass to help small businesses connect with freelance web designers to handle their marketing and project management tasks. The company is growing 40 percent month-over-month with a core team of four people and 40 designers on contract.

In their first year, 2014, revenues hit just $4,000. In 2015, revenues hit $40,000. Over $250,000 worth of projects have been processed through the platform as of mid-2016.

What he wishes he knew when he was 20: Don't believe all the hype.

24. Nathan Klarer, 25 years old, CEO of Bridgecrest Medical

Riding trends can make you rich. Klarer has done just that. After noticing the buzz around wearable technology, he decided to use his engineering degree to create wearable technology for heavy industrial sites. The wearables help managers prevent and minimize accidents in mines and oil rigs.

Klarer is the sole founder of Bridgecrest Medical but has also given equity to other important team members. Together, they've raised $1.3 million, signing 10 customers to five- and six-figure annual contracts.

25. Jennifer Reyna, 26 years old, CEO of Gaszen

Reyna studied business creation and development at a University in Mexico and went on to create three companies: AgriDeliCo (a socio-company), Brain Fusion (embedded software development) and Gaszen (gas management company). She's also a full-time mom.

Gaszen is a piece of measurement hardware that households in Mexico can put on their gas tanks to learn when the tank is almost empty. Reyna then connects gas suppliers with empty tanks and takes a cut. She's raised $700,000 so far.

What she wishes she knew when she was 20: Hard work can make anything and everything happen.

26. Rami El Chamaa, 26 years old, CEO and co-founder of Appointlet

Most people wouldn't choose to look through Reddit threads full of trolls for their co-founder, but that's exactly how Chamaa found his.

After gaining experience in the digital marketing industry at Eastline Marketing and Ernst & Young, Chamaa helped create an appointment scheduling software called Appointlet with co-founder Jared Morse. 1,100 customers pay $30 per month on average, $30,000-plus in monthly revenues. The company is bootstrapped, and Chamaa owns 25 percent of the company.

What he wishes he knew when he was 20: Learn how to learn faster.

27. Steven Mazur, 25 years old, co-founder and CEO of Ash & Anvil

Mazur (5'6") and his 5'8" co-founder wanted clothes for shorter guys, so they founded Ash & Anvil in 2015. Their goal was to raise $10,000 on Indiegogo, which they more than doubled, raising $26,000 in pre-orders.

To date the company is self-funded, run by just the two co-founders, and did $50,000 in total year 1 (2015) sales. An early sign of success: One in every four customers has come back and ordered again.

These 27 young entrepreneurs have proven that age is just a number. Use tactics they've used to set yourself up on the millionaire fast track and remember every big thing starts with something small. If you're under 30 and reading this, your biggest advantage is time: The earlier you start, the more time you have to mess up.

For daily interviews with CEOs young, old and everything in between, listen to The Top Entrepreneurs podcast on iTunes or on Stitcher. If you prefer to read shownotes, you can find those quick summaries here.