401(k) Calculator
Model how employee deferrals, employer match, salary growth, and long-run returns shape a workplace retirement account.
Last updated: March 24, 2026
Financial planning notice
Finance tools are intended for planning and comparison, not as legal, tax, investment, or accounting advice.
Verify assumptions, rates, fees, and statutory rules before using the output in a real decision.
Interactive tool
The live form, validation, and result state for 401(k) Calculator load after the page scripts run. The content below summarizes how the tool works and links to related pages in the catalog.
Estimate 401(k) growth using salary, employee contribution rate, employer match, salary growth, inflation, and long-run investment-return assumptions.
How to use 401(k) Calculator
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1
Enter your inputs into the 401(k) Calculator form.
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2
Adjust optional settings so the scenario matches your real-world case.
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3
Review the result, then tweak one variable at a time to compare outcomes.
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Keep your best scenario as a baseline for future decisions.
Financial calculators provide directional estimates. Confirm decisions with current lender, tax, or regulatory details.
Best use cases
Worked example
Match-focused contribution example
An employee can see how much extra retirement value comes from contributing at least enough to capture the available employer match.
- Start with annual salary and current 401(k) balance, then enter the employee contribution rate.
- Add the employer match rate and the salary percentage the match applies to.
- Review the first-year match and the long-run balance to see whether the current contribution rate is fully using the benefit.
401(k) planning is stronger when employee savings rate and employer match are evaluated together instead of separately.
Methodology
- The calculator estimates first-year employee and employer contribution amounts from salary, contribution rate, match rate, and match cap.
- It then projects long-run growth by treating those contributions as recurring monthly additions that increase with salary growth over time.
- Inflation-adjusted output shows the purchasing power of the projected balance rather than only the future nominal account value.
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