Budgeting on a fixed-income can be stressful.
Many Americans say they'll have financial peace of mind when they have enough money to live comfortably the rest of their lives.
Around 75% of retirees say that uncertainty over having a fully funded retirement is their biggest fiscal stressor, according to the 2020 Four Pillars of the New Retirement study by investment company Edward Jones.
Retiring early means you'll need to fund decades of your life without a steady salary to bolster your budget.
Luckily, if you can save enough money now, you can pay for your retirement by living off returns.
CNBC crunched the numbers, and we can tell you how much you need to save now to safely get $40,000 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.