Do you have $25,000? Would you like to turn it into $436,235? Well, the stock market can do that for you -- and it can powerfully increase the value of just about any investment, whether it's $25,000 or $2,500, or just $250. Here's a look at how it can happen -- for you and anyone else. Image source: Getty Images. It's all math It really is all about math -- and not very complicated math, either. The stock market's average annual return over many decades is close to 10%, though over shorter periods (like 20 years), it can be much higher or lower. So if you invest $25,000 in the stock market and average a 10% annual return, your investment will grow in value to $436,235 over 30 years. The following table shows how it happens: Over This Period, Growing at 10%: $25,000 Will Grow to: 5 years $40,263 10 years $64,844 15 years $104,431 20 years $168,187 25 years $270,868 30 years $436,235 35 years $702,561 40 years $1,131,481 45 years $1,822,262 50 years $2,934,771 55 years $4,726,479 60 years $7,612,041 Source: Calculations by author. You can't count on averaging 10%, though, so let's be a bit more conservative. The following table reflects growth at 8% annually: Over This Period, Growing at 8%: $25,000 Will Grow to: 5 years $36,733 10 years $53,973 15 years $79,304 20 years $116,524 25 years $171,212 30 years $251,566 35 years $369,634 40 years $543,113 45 years $798,011 50 years $1,172,540 55 years $1,722,846 60 years $2,531,427 Source: Calculations by author. Growing at 8%, you'll only reach $251,566 in 30 years. Still, that can be quite a useful sum in retirement. And there's a chance, of course, that you might average 12% or more over your particular investing period. Go ahead and aim high, but don't assume that great returns are in any way guaranteed. Image source: Getty Images. How can you amass $436,235 yourself? So how can you achieve the results above? Clearly, $25,000 in your hand and 30 years may do it. Be sure that you're targeting annual returns that at least roughly match the stock market's average, though -- something that's easy to do if you invest in low-cost, broad-market index funds. For most investors, index funds are the best choice because they're extremely easy to invest in and require little attention. Your money will simply be spread out across lots of companies immediately, giving you diversification and a chance to earn roughly the market's return. If you don't have $25,000 ready to invest, that's OK -- because you can achieve the sums above with far less if you make regular investments in the stock market. Check out the following table: Growing at 8% for: $5,000 Invested Annually $10,000 Invested Annually $15,000 Invested Annually 5 years $31,680 $63,359 $95,039 10 years $78,227 $156,455 $234,682 15 years $146,621 $293,243 $439,864 20 years $247,115 $494,229 $741,344 25 years $394,772 $789,544 $1.2 million 30 years $611,729 $1.2 million $1.8 million 35 years $930,511 $1.9 million $2.8 million 40 years $1.4 million $2.8 million $4.2 million Calculations by author. Simply investing $5,000 each year can get you almost to that $436,235 in only 25 years, not 30 -- and investing $10,000 annually can exceed $436,235 in only 20 years. Investing $15,000 annually -- which might be very doable, especially if yours is a two-income household -- can exceed $436,235 in only 15 years. There are two more things you'll need if you really want to achieve that $436,235 (or more!): patience and determination. Patience is necessary because the big growth in your account will happen in the later years. A glance at any of the tables above will confirm that in the first few five-year periods, your account will grow by tens of thousands, and in the later ones, by hundreds of thousands. Determination is also necessary because without it, you can lose interest, lose faith in the process, or just procrastinate when it comes to investing annually. Believe in your retirement plan and stick with it. It might help to automate some of your investing, too. 10 stocks we like better than WalmartWhen our award-winning analyst team has an investing tip, it can pay to listen. After all, the newsletter they have run for over a decade, Motley Fool Stock Advisor, has tripled the market.* They just revealed what they believe are the ten best stocks for investors to buy right now... and Walmart wasn't one of them! That's right -- they think these 10 stocks are even better buys. See the 10 stocks Stock Advisor returns as of 6/15/21The Motley Fool has a disclosure policy.Source