Almost a quarter of Americans have less than $5,000 saved for retirement.

And to someone with no savings and an annual salary of $75,000, the idea of putting away $2 million for retirement can seem like an impossible goal. It can be done, however, it will take time and dedication.

As a rule of thumb, most financial advisors suggest you save 10% to 15% of your salary. But if your goal is to get to $2 million, the percentage you need to invest will vary widely based on how old you are when you start.

NerdWallet crunched the numbers, and we can tell you exactly how much of your $75,000 you'll need to tuck away to get there.

Just a few things to remember: These numbers assume you have no money in your retirement plan, that you will get an average 6% return on your investments and that you will retire at age 65.

The math also does not account for potential pay increases, employer matches, inflation or any curveballs that life may throw at you. So plan accordingly.

Now let's dive into the figures.

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How to save $2 million for retirement if you make $75,000 a year, broken down by age - CNBC