401(k) Contribution Calculator

A 401(k) combines three powerful forces: your contributions, your employer’s match, and decades of compounding. This calculator projects your balance at retirement and shows how much of it is free moneyfrom your employer’s match.

Percent of salary you contribute.

e.g. 50% means "50 cents per dollar".

Employer matches up to this % of salary.

Projected 401(k) balance$838,730
Your contributions$180,000
Employer match (free money)$67,500
Investment growth$591,230
Projected 401(k) balance grows to about $838,730 over 30 years from your contributions plus the employer match and compounding.

How this calculator works

Your yearly contribution is a percentage of salary:

your contribution = salary × your %

The employer match is typically expressed as “X% of your contribution, up to Y% of salary.” A common example is 50% match up to 6%. We compute it as:

employer match = salary × min(your %, match limit %) × match rate %

The combined amount is then invested and compounded monthly over your years to retirement using the future-value-of-an-annuity formula, with monthly return r over n months:

FV = PMT · ((1 + r)ⁿ − 1) ÷ r

Always capture the full match

An employer match is an immediate, guaranteed return on your money — contributing less than the limit leaves free money on the table. Try raising your contribution to the match limit and watch the employer total jump.

Learn more

Frequently asked questions

What does '50% match up to 6%' mean?
Your employer adds 50 cents for every dollar you contribute, but only on the first 6% of your salary. To get the full match, you'd contribute at least 6% — anything less forfeits part of the free money.
Does this account for contribution limits?
No — the IRS caps annual 401(k) contributions, and the limit changes yearly. This is a simplified projection; very high contribution percentages on a high salary may exceed the legal limit in practice.
Is the projected balance guaranteed?
No. It assumes a steady average return, but real markets fluctuate, and it ignores taxes on withdrawal and inflation. Treat it as an illustration of how contributions plus matching plus compounding add up, not a promise.