It is possible to grow a small amount of money into a significant sum. But it's important to choose wisely and maintain adequate diversification. You can never know with 100% certainty what stocks are going to meet your expectations, but if you put together a portfolio of growth stocks, you increase the odds that one of your stocks will deliver life-changing returns.

That said, here are two growing companies that have the potential to multiply an original investment over the long term.

1. C3.ai

Growing demand for enterprise artificial intelligence (AI) software is a ripe field to look for future winners. Statista sees the AI market overall growing at a 27% annualized rate through 2030, reaching $826 billion. C3.ai (AI -0.19%) is one of the leading providers of enterprise AI software for the U.S. military and large corporations, and its revenue is growing in line with Statista's estimate.

Revenue growth has accelerated for seven consecutive quarters and grew 29% year-over-year in the most recent quarter. A key driver of growth has been strategic partnerships with leading cloud providers, including Microsoft's Azure cloud services business. Microsoft recently expanded its partnership with C3.ai, which bodes well for the company's growth prospects. C3.ai signed 58 agreements last quarter, including ExxonMobil, Coca-Cola, and U.S. government agencies.

The negative for C3.ai is weak profitability. It reported an adjusted net loss of $0.06 per share in the last quarter, and this is weighing on the stock's performance. However, investors can expect profits to follow more revenue growth, as management expects the top line to grow faster than expenses over the long term. If C3.ai delivers, the stock could be worth significantly more in another 10 years.

This is a relatively small business with only $346 million in trailing-12-month revenue, but even though the company is not profitable right now, it ended the quarter with $730 million of cash and short-term investments. Investors that can tolerate near-term volatility in the share price could be well rewarded down the road.

2. Shift4 Payments

Shift4 Payments (FOUR -0.19%) is a fast-growing software and payment processing company. Its primary markets are resorts, restaurants, and sports and entertainment, where it is either the leader or No. 2 player. Quarterly revenue growth has averaged 36% year-over-year over the last two years, pointing to a big opportunity.

A key trend driving the company's growth is merchants moving from using multiple software providers to one system. Some hotels might use one software system for check-in and another for its restaurant, which is inefficient and costly. Shift4 Payments solves this problem by offering a complete end-to-end system that handles everything a merchant needs for payments, security, reporting, analytics, and more.

The company is building a competitive advantage that could sustain strong growth over the long term. It is efficiently expanding by acquiring other businesses that have large pools of customers. After it acquires a company, Shift4 can cross-sell thousands of new customers with bundled services.

The financing to acquire other businesses has left the company saddled with $2.8 billion of long-term debt, but it also has $1.4 billion of cash. It also is starting to see improving margins. Through the first three quarters of 2024, Shift4 reported a 56% year-over-year increase in net income, reaching $113 million.

The stock is following the company's growth, rising 86% over the last three years, and could offer years of compounding returns to shareholders. The stock is trading at 22 times this year's earnings estimate, which is a reasonable valuation for a fast-growing payments company.