Here's exactly how long it will take you to become a millionaire just 4 steps.

Are you on track to become a millionaire?
If you're putting away $415 a month starting in your 20s, $651 a month starting in your 30s or $1,300 starting in your 40s, with a six percent return on investment, you're on the path to hitting that milestone by 67.

Here's exactly how long it will take you to become a millionaire just 4 steps.

But how soon could you become a millionaire if you're able to save more per month? CNN Money's helpful millionaire calculator can give you an idea of how close you are.
Let's assume zero savings and a six percent annual rate of return.
If you start saving $50 a month, it would take 77 years to become a millionaire by July of 2094.
But if you can start putting away $500 per month, you'll be a millionaire in 40 years, by June 2057.
If you're able to sock away $1,000 a month starting today, you'll reach millionaire status in just 30 years, by May 2047. 
Try out the calculator yourself here.
These differences speak to the power of compound interest, in which any interest earned accrues interest on itself, and a little money invested now can amount to more than a lot of money invested later. In short: If you want to become a millionaire, the earlier you start investing, the better.
Of course, this calculation doesn't account for the many variables that can affect your wealth over several decades, including windfalls, emergencies and rises or dips in the market. But it can give you a good estimation of whether or not you're saving enough to retire comfortably. 
Ready to put your money to work? The simplest starting point is to invest in your employer's 401(k) plan, a tax-advantaged retirement savings account. Next, consider alternate retirement savings accounts, such as a Roth IRA, traditional IRA and/or a health savings account.
You can also research low-cost index funds, which Warren Buffett recommends, and online investment platforms known as robo-advisers.
 If you want to be a millionaire, start thinking like one

Millionaires think long term

Wealthy people don't only think about the present. They also consider the potential of the future. That means setting goals that might span years or decades, not just weeks or months. According to Smith, the longer you can stretch your thinking into the future, the richer you will become.

That's because long-term goals force you to grapple with big-picture questions such as, "How can I double my income this year?" instead of short-term issues, such as, "How am I going to pay my bills this month?"

Smith finds that millionaires are willing to put temporary comfort on hold to seek out long-term financial freedom. And that mindset speaks to an important trait many millionaires share: patience.

"Middle-class people want instant gratification," Smith writes. "I was like that for many years. Whatever I wanted, I charged to my credit card or put a little bit down and made payments on the balance. Now I wait for the things I want because my goal is more freedom, not comfort.

"Rich and very rich people have developed the discipline of delayed gratification."

Millionaires embrace change

Whether small or big, change can be intimidating. While the middle class tends to fear change, millionaires view any type of change as opportunity, Smith says.

"The problem with the middle class is it assumes change will be negative most of the time," Smith writes. "Millionaires assume that all change, positive or negative, will benefit them."

Learning to welcome change, and welcome the growth that often accompanies it, builds confidence, which Smith says is key.

"Confidence is acquired through preparation and hard work," Smith writes. "Confidence is the result of working on yourself. It is the benefit of proving yourself to yourself. It is knowing you can handle whatever comes your way."

Millionaires never stop learning

Walk into any millionaire's home and you're likely to find an abundance of books, if not an entire library, Smith observes. That's because millionaires know that learning doesn't stop when you finish school.

"Success is a process," Smith says. "If a percentage of your income isn't going toward a financial education, you will stay trapped in the middle class. The more money you spend on financial knowledge, the more money you will make."

The cheapest and easiest way to start investing in your financial education is through books. "Are you aware that you can learn a concept in only a few hours from a book that took someone years to develop?" Smith writes.

"I feel like some of the $20 books I have read were worth $20,000 because of what I learned from them," he adds.

Millionaires ask themselves empowering questions

The No. 1 difference Smith observes between millionaires and the middle class is how millionaires present information to themselves. While millionaires ask themselves empowering questions, the middle class tends to lean toward disempowering ones.

Millionaires ponder, "How can I make $1 million a year doing what I love?" while middle class people stick to the practical: "How can I get my boss to give me a raise?" Millionaires look at a hard situation and ask, "What is life trying to teach me right now?" while the middle class tends to focus on, "Why do bad things always happen to me?"

The distinction between these sets of questions is subtle but crucial. "Empowering questions ask what you can do, and disempowering questions ask what you can't do," Smith writes.

"Empowering questions cause you to reach for your full potential," he continues. "The questions you ask yourself determine the results you get in life."

How you frame situations informs how you handle them. "Millionaires are more creative than reactive," Smith writes. Instead of simply taking things as they come, millionaires focus on how they can make the future different — and better.