How to use the 401(k) calculator
- Enter current balance, salary, your deferral %, employer match % and match cap % of salary.
- Set years until retirement and a constant growth rate.
- Read projected balance and total employer contributions over the horizon.
What is modeled
Level salary, monthly deferrals, and match on eligible deferrals up to the cap—compounded monthly at your rate. No IRS dollar limits, catch-up contributions, vesting cliffs, or loan withdrawals.
Example
$25k balance, $75k salary, 6% deferral, 50% match on first 6% of salary, 7% growth, 20 years → ending balance in the mid six figures on typical defaults (see form).
Related
Broader retirement modes: retirement calculator. Custom schedules: compound interest.
Frequently asked questions
What does this 401(k) calculator include?
Salary deferral as a % of pay, employer match as a % of your deferral up to a salary cap, years until retirement, and a flat growth rate with monthly compounding—simplified.
What is not modeled?
No IRS dollar limits, catch-up contributions, vesting cliffs, loans, withdrawals, or changing salary over time. Use as a directional projection, not a plan document.
How should I read employer match?
Match applies to eligible deferrals up to the cap % of salary you enter—common pattern “50% match on first 6%.” If your plan differs, adjust the match and cap fields to approximate.
What growth rate should I use?
A long-run average return assumption for a diversified portfolio—lower for conservative planning. Not a forecast or guarantee.
How does this relate to other tools?
Broader retirement modes: retirement calculator. Custom schedules: compound interest. Forward lump-sum growth: future value.
Can I share my scenario?
Yes. Use copy link below the form to share the same numbers with someone else or keep the scenario for your records.