Investing in the right growth stocks can help you build tremendous wealth. All it takes is patiently holding shares of a business that generates significant growth in revenue and profits over the long term.

But there are a lot of solid growth stocks out there. To find the stocks that can deliver massive upside, you want to look for companies that are bringing something new to the marketplace in a way where they don't face much competition.

To give you some ideas, here are two high-growth companies that could make early investors a lot of money over the next 10 years.

A businessperson standing on top of a large cash pile holding a flag.

Image source: Getty Images.

1. SoundHound AI

There's a huge opportunity for artificial intelligence (AI)-driven voice assistants to improve the customer experience for many businesses. SoundHound AI (SOUN 2.70%) has been reporting extremely high revenue growth rates from selling its voice AI solutions to quick-service restaurants and leading automakers. The stock is poised to climb higher after more than doubling over the past year.

SoundHound reported another record quarter in Q2, with revenue up 217% year over year. The main negative is that the company continues to report losses on the bottom line, but on an adjusted EBITDA (earnings before interest, taxes, depreciation, and amortization) basis, its losses narrowed and management expects this profit metric to turn positive by the end of the year.

This strong growth clearly signals that companies are finding tremendous value in adopting conversational voice assistants. All of SoundHound's primary business channels posted strong growth, including automotive, AI customer service for enterprise, and restaurants.

Just recently, SoundHound added vision capabilities to its voice AI platform. This will enable businesses to use SoundHound for more use cases, such as equipment troubleshooting, retail inventory intelligence, and more personalized assistance while driving.

Most importantly, the addition of vision AI to its voice capabilities indicates that SoundHound's long-term growth opportunity is bigger than originally thought. As management continues to invest in its technology, the upside for investors could be tremendous over the next decade, especially with the stock trading at a relatively low market cap of just $5 billion.

2. Reddit

Reddit (RDDT -0.60%) has a highly engaged community of users that visit the platform every day to discuss an almost infinite number of topics. Its discussion-based platform is what separates Reddit from all the other social media platforms, and it's why the business could be significantly more valuable in another decade than it is today.

Reddit exceeded expectations last quarter, with revenue surging 78% year over year in Q2. Daily active unique users grew 21% year over year to over 110 million. Many of these users are using Reddit to get feedback on products they are interested in buying, while others are looking to connect with others on a wide range of topics. This vibrant community is attracting advertisers, with ad revenue surging 84% over the year-ago quarter.

Reddit has a long runway of growth. It is operating in a $700 billion digital advertising market, where social media ad spending alone is estimated at $276 billion, according to Statista. However, Reddit is still very small relative to the total amount of digital ad spending. It generated just $1.6 billion in trailing-12-month revenue, which means it can potentially sustain high double-digit growth for many years.

Still, the social media ad market doesn't fully capture Reddit's opportunity. Its discussion-based platform is gaining a lot of data. This is opening up growth opportunities to license its data to AI model makers, where its "other" revenue grew 24% year over year in Q2. This underscores the value embedded in its data and opens up opportunities for Reddit to diversify beyond advertising over time.

The ability to potentially capture interest from almost anyone in the world looking for information online could make Reddit a significantly more valuable platform over the long term. At the rate the company is growing, investors are looking at substantial returns over the next decade.