How a 401(k) grows
A 401(k) grows from three sources: your own pre-tax contributions, your employer's match, and investment returns compounding over time. Because contributions come out before tax and grow tax-deferred, more of your money stays invested — which is why 401(k)s are one of the most powerful wealth-building tools available to employees.
Always capture the full match
An employer match is free money — a 100% instant return on the portion they match. If your employer matches up to a percentage of salary, contributing at least that much should be the first priority in any savings plan. This calculator caps the match at your contribution rate, mirroring how matches actually work.
Why starting early wins
Decades of compounding do the heavy lifting: the growth line bends sharply upward toward retirement, so early contributions matter far more than later ones. The 'investment growth' figure often ends up larger than everything you and your employer put in combined — that's compounding rewarding time in the market.
Assumptions and limits
This projects steady growth at your assumed return; real markets fluctuate, and contribution limits, vesting schedules and fees apply. Returns and salary aren't guaranteed. Treat the figure as a planning estimate and revisit it as your salary or contribution rate changes.
Frequently asked questions
How much will my 401(k) be worth?
It depends on your salary, contribution rate, employer match, years invested and return. This calculator compounds your contributions plus the match at your expected return to project the balance.
How does an employer match work?
Your employer contributes an amount tied to yours, usually up to a percentage of salary. It's effectively free money, so contributing enough to get the full match should come first.
What return should I assume?
A long-run stock-heavy 401(k) has historically returned roughly 7% after inflation, but this varies and isn't guaranteed. Use a conservative figure and treat the result as an estimate.
Does this include contribution limits?
No — it doesn't cap contributions at the annual IRS limit or model vesting and fees. Check current limits and your plan's rules for a precise picture.