The formula
How it works
Project how large your 401(k) will grow by retirement, including your employer’s matching contributions. The match is free money, and combined with decades of compounding it can more than double your own savings.
FAQ
Why is the employer match so valuable?
It is an instant, guaranteed return on your contribution — often 50% or 100% of what you put in, up to a limit. Not contributing enough to get the full match means leaving free money on the table.
How much should I contribute?
At least enough to get the full employer match. Beyond that, aim for 10–15% of your salary if you can. The earlier you start, the more decades of compounding work in your favour.
Is there a limit to how much I can contribute?
Yes, the IRS sets an annual cap on employee contributions, with a higher “catch-up” limit for those 50 and older. Employer matches are separate and don’t count against your personal contribution limit.
What’s the difference between a traditional and a Roth 401(k)?
A traditional 401(k) is funded with pre-tax dollars and taxed on withdrawal, while a Roth 401(k) is funded with after-tax dollars and grows tax-free. This calculator projects the account balance itself, which works the same way for either type.
What is vesting and why does it matter?
Vesting is the schedule that determines how much of the employer match you actually keep if you leave the job early — your own contributions are always fully yours. Unvested match dollars are forfeited, so it’s worth checking your plan’s vesting schedule.
What happens to my 401(k) if I change jobs?
You can typically leave it with the old plan, roll it into your new employer’s 401(k), or roll it into an IRA without triggering taxes. Cashing it out instead usually means income tax plus an early withdrawal penalty if you’re under 59½.
How much do fees affect the projected balance?
Fund and account fees are deducted from your return before it compounds, so even a 1% annual fee can shave off a large chunk of the final balance over 20–30 years. This calculator assumes the return you enter is already net of fees.
About the 401(k) calculator
This calculator projects the future value of a 401(k) retirement account, taking into account your own contributions, your employer’s match, your current balance and years of investment growth. A 401(k) is one of the most powerful savings tools available, because contributions are made before tax and many employers match part of what you put in. Seeing the projected balance shows just how much those matched, tax-advantaged dollars can grow.
How to use it
Enter your salary, the percentage of it you contribute, your employer’s match percentage, your current balance, the return you expect, and how many years until you retire. The calculator adds your contribution and the match together each year and grows them at your chosen return. For example, a $60,000 salary with a 6% contribution and 3% match, starting from $20,000 at a 7% return over 30 years, can build a balance well over half a million dollars.
The formula
The balance combines the growth of your current savings and your yearly contributions: , where is the current balance, is the total yearly contribution (yours plus the employer match), is the annual return and is the years to retirement. The match is simply your employer’s percentage of salary added to your own contribution each year before it compounds.
Where it is used
Employees use it to plan how much to contribute and to see the long-term payoff of capturing the full employer match. Financial advisers use similar projections to build retirement plans, and it helps compare contributing to a 401(k) against other savings. Because the match and the tax advantages compound over decades, running the numbers early is one of the highest-value moves in personal finance.