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401(k) Calculator

Project your 401(k) balance at retirement with employer match and compound growth.

Projected Balance at Retirement

$982,392

in 30 years

Your Contributions

$240,000

$8,000/yr · $667/mo

Employer Match

$72,000

$2,400/yr · $200/mo

Investment Growth

$670,392

at 7% annual return

Total annual contribution: $10,400
Total monthly contribution: $867

Before-tax contributions. Consult a financial advisor before making investment decisions.

Year-by-Year Balance

YearProjected BalanceYour TotalMatch Total
Year 5$59,808$40,000$12,000
Year 10$143,691$80,000$24,000
Year 15$261,342$120,000$36,000
Year 20$426,353$160,000$48,000
Year 25$657,790$200,000$60,000
Year 30$982,392$240,000$72,000

About the 401(k) Calculator

This 401(k) calculator estimates your retirement balance using compound interest applied to both your current balance and your ongoing contributions. It factors in your annual salary, your personal contribution percentage, and your employer's matching contribution (up to a specified percentage of your salary). The projected balance assumes a fixed annual rate of return and that contributions are made consistently throughout your working years. Use it to model different scenarios — such as increasing your contribution rate or starting earlier — to see how small changes compound significantly over time.

Built and maintained by Meet Shah · Last updated

What this tool is used for

  • Seeing how a contribution rate change affects a projected balance.
  • Understanding how much an employer match contributes over time.
  • Comparing two return assumptions on the same contributions.
  • Getting a figure to check against a provider's own projection.
  • Seeing the effect of starting a few years earlier.

Frequently Asked Questions

What is the employer match worth?
An immediate 50–100% return on the matched portion, which no investment reliably provides. Contributing less than the full match is the one unambiguous mistake in retirement saving — it is declining part of your stated compensation.
Traditional or Roth?
Traditional deducts now and taxes withdrawals; Roth taxes now and withdraws tax-free. The decision is a bet on your marginal rate then versus now — Roth generally wins early in a career when the rate is low, traditional at peak earnings.
What is vesting?
The schedule on which employer contributions become yours. Your own contributions are always fully yours; the match may take three to six years to vest, on a cliff or graded schedule. Leaving before it completes forfeits the unvested part entirely.
Why do fees matter more than they look?
Because they compound against you. A 1% annual fee against a 7% return removes roughly a quarter of the final balance over 35 years — not 1%. It is the single largest controllable variable in a long-horizon account.
What happens if I withdraw early?
Income tax plus a 10% penalty before 59½, with narrow exceptions. The larger cost is invisible: the withdrawn amount stops compounding, so £10,000 taken at 30 is closer to £100,000 of foregone balance at 65 at historical returns.

Common errors and gotchas

  • Treating a projection as a forecast, when returns are variable and the figure is illustrative.
  • Using a single average return, which hides sequence-of-returns risk entirely.
  • Ignoring fees, which compound against you exactly as returns compound for you.
  • Omitting the contribution limit, which caps what the projection assumes.
  • Forgetting the balance is pre-tax, so the spendable amount is lower.

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