Here's How I Double My Net Worth Every 10 Years

I've tried day trading and a few of those "get rich quick" ideas. Spoiler: none of them worked.

What has worked is the slow, steady stuff. Investing my money into broad index funds and letting compound interest do its thing.

My whole money goal now is pretty simple. I just want to double my net worth every 10 years. And a steady 7% return is enough to get me there.

The simple math behind it (aka the Rule of 72)

There's this fun little shortcut I learned years ago called the Rule of 72.

Here's how it works: Divide 72 by your average annual return, and the result tells you how long it'll take to double your money.

So:

• A 1% return takes 72 years to double your money.
• A 4% return takes 18 years.
• And a 7.2% return takes right around 10 years.

It's kind of wild when you think about it. Give your money a few decades, and it keeps doubling again and again.

Here's what $10,000 can grow into with a steady 7.2% return:

Once I wrapped my head around compounding, I started saving more. It's wild to realize that every $1,000 you tuck away today could become about $8,000 in a few decades -- just by leaving it alone.

Why I stick with index funds

Over the years, I've tried a bunch of investing styles. I've chased big wins with hot stocks (and totally flopped). I've played the rental property game (and barely broke even with some places).

Eventually, I landed on my favorite strategy: "index and chill."

Index funds are easy to buy, highly diversified, and hands-off. Instead of deciding exact stocks or industries to put money into, index funds spread my money around so I'm invested in a little bit of everything.

Most of my long-term money sits in a broad market index fund, similar to the S&P 500. Historically, that's averaged around 10% per year. Even if future returns are a little lower, it's still enough to hit my "double every decade" goal.

Automation and tracking my progress

I invest like a robot. Every single month like clockwork, I send money into my 401(k), Roth IRA and brokerage accounts.

The nice thing about index funds is you can buy them in tiny pieces. So whether I'm adding $1,000, $100, or even just $10, it's all going toward the same fund.

And to stay motivated, I check my net worth every couple of months. This is just a quick calculation of all my investments and assets, minus my loans and debts.

Working out this number helps me see the bigger picture. As long as it's trending up over time, I know I'm moving in the right direction.

There have been years when my net worth has gone down (stocks go up and down), but over the long haul it's always grown and has a positive average.

The bottom line

Every dollar that I save and invest today is on track to double every 10 years.

It sounds slow and boring, but over time that boring stuff turns into something pretty incredible.

If you're ready to start building your own long-term plan, check out our best investment apps for beginners in 2025 -- including my top pick for hands-off index investing.