This ETF Could Make You a Millionaire With No Investing Knowledge at All

You can make a lot of money in the stock market. If you have investing knowledge, you can pick individual companies to buy shares of and hopefully earn very competitive returns that significantly increase your net worth.

But you don't have to be an investing guru in order to put your money to work in the market.

In fact, you can buy certain kinds of assets with essentially no knowledge that are all but guaranteed to make you a millionaire over time. Here's one of the assets that can make that happen.

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Want to become a millionaire? Put your money into this ETF

ETFs, or exchange-traded funds, are traded just like stocks. You can open a brokerage account, put a little bit of money into it, and buy and sell ETFs with the click of a button anytime the market is open.

But, when you buy an ETF, your money doesn't just buy you an ownership stake in one company. Each owner of an exchange-traded fund has a very small ownership share in a large number of assets the ETF owns.

If you want to become a millionaire without knowing anything about investing, your best bet may be to buy an ETF that tracks the performance of a financial index called the S&P 500. The S&P 500 is made up of around 500 large U.S. companies including Apple, Microsoft, and Tesla. The companies that are part of this index are household names. They come from every sector of the economy.

When you buy an S&P 500 index fund, you own a little bit of all of them. You're essentially putting your money into big business in America. And you're taking very little risk since the S&P 500 has a very consistent performance track record of producing average annual returns of around 10% over the long term.

Now, there are different S&P 500 ETFs to chose from, so you'll want to look at the expense ratio of each one. That's the cost to invest and it's typically very low. The Vanguard S&P 500 ETF (VOO -1.04%) is one of the best choices, as it has an expense ratio of 0.03% as well as a consistent track record of following the performance of the S&P.

How much do you need to invest in this ETF to become a millionaire?

When you buy Vanguard's S&P ETF, or any other ETF that tracks the performance of the same financial index, you can sit back, let your money grow, and wait to amass a seven-figure nest egg. The only question is, how much do you need to invest? And that can vary depending on when you got started.

Let's say you earn around the 10% average annul return over time that you can reasonably expect. The table below shows the amount you'd need to put into your fund to reach millionaire status given your investing timeline.

Calculations by author via investor.gov.

Investing the amount mentioned in the table above is likely all you need to do. You don't need to know how to pick stocks, do too much monitoring of your portfolio, or make regular changes to your investment mix. It's the most effortless a way to become a millionaire short of being born one.