How to use the 401(k) Calculator
- Enter your Current balance.
- Enter your Annual contribution.
- Enter the Employer match rate (e.g. 0.5 = 50¢ per $1).
- Enter your Expected annual return.
- Enter Years until retirement.
- Read the projected balance below.
Worked example
You have $25,000 saved, contribute $10,000 a year, your employer matches 50%, you assume 7% growth, and you have 25 years to go.
- Current balance: $25,000; Annual contribution: $10,000
- Employer match: 0.50×; Expected return: 7%; Years: 25
Result: $1,084,421 at retirement — employer matching alone adds a large chunk of that.
How a 401(k) grows
Your 401(k) compounds in two ways: your existing balance grows, and every year you (and your employer) add new money that then grows too. Employer match is essentially free money, which is why maximizing it is the highest-return move available.
The projection formula
FV = B(1+r)t + (C + M) × [((1+r)t − 1) / r]
B = current balance, C = your annual contribution, M = employer match, r = annual return, t = years.
Frequently asked questions
What if my employer matches only up to a limit?
This calculator applies the match rate to your full contribution. If your plan caps match at, say, 6% of salary, reduce your contribution input to that capped amount for a realistic figure.
Should I include catch-up contributions?
If you're 50 or older you can contribute extra. Add that to the annual contribution field for a more accurate total.
Is the result taxable?
Withdrawals from a traditional 401(k) are taxed as ordinary income in retirement. Roth 401(k) withdrawals are tax-free. This tool shows pre-tax nominal growth.