We would probably like to be rich by retirement, if not a whole lot sooner. It's hard to do it any way other than being diligent about saving and investing, and for best results, consider parking your dollars (that you won't need for at least five years) in the stock market.

You can achieve solid results simply by investing in one or more low-fee, broad-market index funds, such as one that tracks the S&P 500. The overall stock market has averaged roughly 10% annual growth over many decades, though you'll likely average more or less than that over shorter periods.

If you want to aim for even more robust growth, and assuming you have at least five, if not 10 or more, years to go before retirement, look at individual stocks. Here are three contenders to consider. Be sure to research any of interest further before investing, of course.

1. PayPal

PayPal Holdings (PYPL 2.90%) had a recent market value topping $60 billion. It's a digital payment specialist with 435 million active consumer and merchant accounts, 22.3 billion transactions, and $1.36 trillion in total payment volume (TPV) as of the end of 2022.

In its third quarter, PayPal reported total TPV close to $400 billion, up 15% year over year, with revenue increasing by 8%. (Those numbers are 13% and 9%, respectively, when adjusted for currency exchange.)

The company has faced some challenges recently, like increased competition and a reduced dependence on online purchasing after the onset of the pandemic. The previous CEO started shifting the company's focus, from acquiring more customers, to getting more business from existing customers -- which seems to have been a profitable move.

PayPal's stock was recently down more than 80% from its all-time high, but it has a new CEO as of September, Alex Chriss from Intuit, and there's still a lot to like about the growing fintech company -- such as a compellingly low valuation.

2. The Trade Desk

The Trade Desk (TTD 1.67%), with a recent market value topping $30 billion, specializes in digital advertising, running a cloud-based platform that lets customers post ads.

The market for digital advertising is huge, with growth expected to go from $243 billion in 2017 to more than $900 billion by 2027. The company has grown with this market -- so much so that someone putting $1,000 into it at its 2016 initial public offering would now have an investment worth more than $23,000.

In the third quarter, revenue grew 25% year over year, and management said customer retention remained over 95% during the third quarter, as it has for the past nine consecutive years. That's pretty impressive!

Trade Desk bulls have grown even more bullish, because the company has released a new platform called Kokai, driven by artificial intelligence (AI). Its other promising initiatives include developing a replacement for third-party cookies, which are departing Google's Chrome soon.

Best of all, The Trade Desk's stock recently dropped more than 15%, presenting an attractive buying opportunity for long-term investors.

3. Etsy

Etsy (ETSY 0.34%) is a major player in e-commerce, with a recent market value topping $8.5 billion. Its focus has long been on handmade and vintage items, but there's more to it than that.

Unfortunately for the company, the market hasn't been impressed with its earnings lately, and the stock recently dropped more than 50% from its 52-week high.

Don't count the company out, though. Yes, near-term projections are relatively weak, due in part to inflation and high interest rates pressuring consumers. And there's more competition than ever in e-commerce, including from Amazon.

But Etsy has been growing its users and is a capital-light business, generating hundreds of millions of dollars in free cash flow. It's also working on improving its search engine for customers, including incorporating AI.

Give these three tech companies a closer look to see if any deserve berths in your long-term portfolio. If you believe in their growth potential, consider buying -- but prepare to be patient, as the best performers make shareholders wealthy over many years, not just a few months.

Remember, too, that you can always take the simpler and easier route, which is also likely to deliver solid results -- index funds, which instantly plug you into much of or all of the stock market. Just keep investing and being patient.