The official retirement age for most Americans is 67 years old.
But that number largely matters for Social Security benefits. If you want to retire early, however, you will need a plan that relies primarily on your own savings and investments.
Luckily, if you can save enough money now, you can fund your retirement by living off returns without draining your nest egg.
CNBC crunched the numbers, and we can tell you how much you need to save now to safely get $75,000 of passive income every year in retirement.
First, some ground rules. The numbers assume you will retire at 45, have no money in savings now and plan to save a substantial amount of income to reach your goal.
For investing, we assume an annual 4% return when you are saving. We do not factor in inflation, taxes or any additional income you may get from Social Security and your 401(k).
In retirement, we use the "4% rule," which is a general principle that says you can comfortably withdraw 4% of your portfolio every year.
It is important to note with the recent market volatility, there is a risk you'll have to lower your spending percentage in the future.
Check out this video to get a full breakdown of the numbers.
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Disclosure: NBCUniversal and Comcast Ventures are investors in Acorns.