Most of today’s workers expect they’ll need at least $1 million to retire, but saving that much can feel impossible, especially if you’re juggling bills and more immediate financial goals. Even those who save diligently can feel like they’re off track because your savings may appear to grow slowly at first.

The good news is that over time, your investment earnings can really add up. You might not need to save as much of your own money as you think to wind up a millionaire by retirement, but that depends on a few key factors.

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Here’s how much you need right now to retire with $1 million

Your personal retirement contributions combine with your investment earnings to equal your total nest egg. The more your investments grow, the less of your own money you’ll need to invest to reach your goal.

The table below breaks down how much you need to have in savings today to have $1 million by the time you retire, based on different average annual rates of return. Because everyone’s monthly retirement contributions are different, these estimates assume you don’t contribute another dime between now and retirement.

Data source: Author’s personal calculations. Dollar amounts are rounded to the nearest dollar.

Don’t panic if you haven’t reached these savings targets. Most people will continue to set aside money for retirement as they’re able to, and that will reduce their savings goal. Also, if you’re married, you’ll have a partner who can hopefully help you save for your shared retirement expenses.

Similarly, don’t get overconfident if you’re already at or over the goal amount listed here, especially if you’re focusing on the 10% average annual rate of return column. Though the S&P 500 has averaged around 10% per year over the last several decades, there’s no guarantee it will continue to perform in the same way. Plus, the above goals only get you to $1 million, and you may need more than that to retire comfortably.

How to calculate what you need

These numbers can give you a rough benchmark of how you’re doing, but having a personalized retirement plan and savings goal to aim for is a better solution. There are different ways of going about this.

One popular strategy is to estimate what your annual living expenses, minus income from sources like Social Security or a pension, will be in your first year of retirement. Then, multiply this amount by 25. The result is the total you need to save. It’s supposed to help your money last at least 30 years.

You could also use a retirement calculator. This gives you the added bonus of providing you with a monthly savings target if you’re not sure how much you should be setting aside right now. If this target isn’t feasible for you, you can always adjust your planned retirement date until you find something that works for you.

Having some sort of a plan can give you a sense of direction and peace of mind, but be prepared to adapt over time. Your retirement goals might change, your income might fluctuate, and even the future of Social Security is uncertain. Check in with yourself at least annually and whenever you experience a major financial shakeup, and adjust your retirement savings plan accordingly.

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