Simple 401k Calculator

How much should you have in your 401(k) by age?

A widely cited benchmark suggests having about 1× your salary saved by 30, 3× by 40, 6× by 50, 8× by 60, and 10× by 67. These are rough guideposts, not rules. Your real target depends on when you plan to retire, your other savings, and the income you want to replace.

What return should you assume?

There is no guaranteed number, but many long-term projections use about 7%. The S&P 500 has returned roughly 10% a year on average over the long run, and around 7% once you subtract inflation. Choosing a lower, more conservative rate builds in a margin of safety if future returns disappoint. The calculator defaults to 7% because it’s a reasonable stand-in for long-run stock returns after inflation.

Traditional vs Roth: which should you choose?

It comes down to when you pay tax. Traditional contributions are pre-tax and lower your taxable income now, but withdrawals are taxed later. Roth contributions are after-tax with no break today, yet qualified withdrawals are tax-free. Roth tends to favor savers who expect a higher tax rate in retirement than they pay today.