401(k) Calculator
Project your retirement savings with employer match, vesting schedules, and compound growth
401(k) Settings
Percentage of salary you contribute each year
% of your contribution matched
Max salary % employer matches
Projection Results
Projected 401(k) Balance at Retirement
$2,210,844.13
Your Contributions
$453.47K
Employer Match (Vested)
$136.04K
Investment Earnings
$1.61M
Growth Multiple
3.66x
Contribution Breakdown
Growth Schedule (Every 5 Years)
| Age | Salary | You | Match | Balance |
|---|---|---|---|---|
| 35 | $84.41K | $8.44K | $2.53K | $84.49K |
| 40 | $97.86K | $9.79K | $2.94K | $192.05K |
| 45 | $113.44K | $11.34K | $3.40K | $354.64K |
| 50 | $131.51K | $13.15K | $3.95K | $596.25K |
| 55 | $152.46K | $15.25K | $4.57K | $950.87K |
| 60 | $176.74K | $17.67K | $5.30K | $1.47M |
| 65 | $204.89K | $20.49K | $6.15K | $2.21M |
Complete Guide to 401(k) Retirement Planning
What is a 401(k)?
A 401(k) is a tax-advantaged retirement savings plan sponsored by your employer. You contribute a percentage of your pre-tax salary, which reduces your current taxable income. The money grows tax-deferred until you withdraw it in retirement, typically after age 59½.
The real power of a 401(k) comes from employer matching contributions and decades of tax-deferred compound growth. Even a modest 50% match on 6% of salary can add hundreds of thousands of dollars over a career. Compare this with after-tax accounts using our Roth IRA Calculator to see the difference between pre-tax and post-tax retirement strategies.
401(k) Growth Formula
Year-by-Year Accumulation:
Balance(t) = (Balance(t-1) + EmpContrib + VestedMatch) × (1 + r)
EmpContrib = Salary(t) × ContribRate
Match = min(EmpContrib, Salary(t) × MatchLimit) × MatchRate
VestedMatch = Match × VestingPct(t)
Where: r = annual return rate, Salary(t) grows by the annual raise percentage each year, VestingPct depends on your employer's vesting schedule
Salary growth compounds your contributions over time, while employer matching and vesting determine how much free money you actually keep. Use our Compound Interest Calculator to explore how different return rates affect long-term growth.
Benefits of Maximizing Your 401(k)
Free Employer Money
Employer matching is an immediate 50-100% return on your contribution. Not contributing enough to get the full match is leaving part of your compensation on the table.
Tax-Deferred Compounding
Contributions reduce your taxable income now, and all gains compound without annual tax drag. Over 30+ years, tax deferral alone can boost your ending balance by 25-40% versus a taxable account.
Automatic Discipline
Payroll deductions invest before you see the money, eliminating the temptation to spend. Behavioral finance research shows automatic enrollment dramatically increases retirement readiness.
Creditor Protection
401(k) assets are protected from creditors under ERISA, providing an additional layer of security that taxable brokerage accounts and even some IRA accounts do not offer.
Tips for Optimizing Your 401(k)
Always Get the Full Match: At minimum, contribute enough to capture 100% of employer matching. A 50% match on 6% of salary means contribute at least 6% — that match is an instant 50% return before any market gains.
Increase with Raises: Bump your contribution rate by 1% every time you get a raise. You will not miss income you never had, and the compounding effect over decades is substantial. Check our Retirement Savings Calculator to model different savings rates.
Watch Your Fees: 401(k) plans often have higher expense ratios than retail index funds. A 1% fee difference compounds to six figures over a career. Use our Expense Ratio Calculator to see the long-term impact of fund fees.
Common 401(k) Mistakes
Leaving Match Money on the Table
Contributing below the employer match threshold means forgoing free money. If your employer matches 50% on the first 6% and you only contribute 3%, you are missing half the available match every single year.
Cashing Out When Changing Jobs
Withdrawing your 401(k) balance when leaving an employer triggers ordinary income tax plus a 10% early withdrawal penalty if under 59½. A $50,000 cash-out could cost $15,000+ in taxes and penalties, plus the lost decades of compounding on that amount.
Ignoring Asset Allocation
Many participants leave contributions in the default money market or stable value fund, which barely beats inflation. Younger investors with 20-30+ years to retirement should typically allocate heavily to equity index funds for higher long-term growth.
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OpenFrequently Asked Questions
What is a 401(k) and how does it work?
A 401(k) is an employer-sponsored retirement savings plan that lets you contribute a percentage of your pre-tax salary. Contributions and investment gains grow tax-deferred until withdrawal in retirement. Many employers also offer matching contributions up to a certain percentage of your salary, which is essentially free money toward your retirement.
How is 401(k) growth calculated?
Each year, your balance grows by: Balance = (Previous Balance + Employee Contribution + Vested Employer Match) × (1 + Return Rate). The employee contribution equals Salary × Contribution Rate. The employer match equals min(Employee Contribution, Salary × Match Limit) × Match Rate, multiplied by your vesting percentage for that year.
What is employer match and how does vesting work?
Employer match is the amount your company contributes to your 401(k) based on your own contributions. A common structure is 50% match on the first 6% of salary. Vesting determines when you own the employer match: immediate vesting means you own it right away, a 3-year cliff means you get 0% until year 3 then 100%, and graded vesting increases ownership gradually (e.g., 20% per year over 6 years).
What are the 401(k) contribution limits?
For 2024-2025, the employee contribution limit is $23,000 per year ($30,500 if age 50+ with catch-up contributions). The total combined limit (employee + employer) is $69,000 ($76,500 with catch-up). These limits are adjusted annually for inflation by the IRS.
What common mistakes do people make with their 401(k)?
Three costly mistakes: (1) Not contributing enough to get the full employer match — leaving the match on the table is forgoing free money. (2) Cashing out when changing jobs instead of rolling over to an IRA or new employer’s plan, which triggers taxes plus a 10% early withdrawal penalty. (3) Being too conservative with asset allocation when young, missing decades of equity market growth.
Can you show a worked example of 401(k) growth?
Starting at age 30 with $15,000 balance, $75,000 salary, 10% contribution rate, 50% employer match on first 6%, 7% return, 3% salary growth, immediate vesting: Year 1 employee contribution = $7,500, employer match = min($7,500, $4,500) × 50% = $2,250, total added = $9,750, end balance = ($15,000 + $9,750) × 1.07 = $26,482.50. Over 35 years, compounding and salary growth drive the balance well past $1 million.