Employee Contribution
$800.00
Employer Match
$500.00
Total Annual Contrib
$1,300.00
How it works
The 401(k) Contribution Optimizer calculates your optimal pre-tax 401(k) contribution percentage to maximize your employer match, minimize current tax liability, and project the long-term account value. It also compares traditional (pre-tax) vs. Roth 401(k) contributions.
Leaving employer match money on the table is one of the most common and costly personal finance mistakes. If your employer matches 100% of contributions up to 4% of salary, contributing less than 4% means forfeiting free money. This calculator identifies your match threshold and models the full impact of contribution level changes.
How to use it: enter your annual salary, current 401(k) contribution %, employer match formula (e.g., 100% match up to 4% of salary), current 401(k) balance, years to retirement, and expected annual return. The calculator shows: - Amount to contribute to capture full employer match - 2024 IRS contribution limits ($23,000, or $30,500 if age 50+) - Annual tax savings from pre-tax contributions (at your marginal rate) - Projected account value at retirement - Roth vs. traditional comparison (pay tax now vs. at withdrawal)
Roth vs. traditional decision: if you expect to be in a higher tax bracket in retirement than today, Roth is advantageous. If you expect a lower bracket in retirement, traditional pre-tax saves more. The calculator shows the break-even tax rate and projects the after-tax value of each option.
Privacy: income and retirement data runs in the browser.
Frequently Asked Questions
- The 2024 IRS 401(k) elective deferral limit is $23,000 for employees. Those age 50 and older can make an additional $7,500 catch-up contribution, for a total of $30,500. The total annual additions limit (including employer contributions) is $69,000 ($76,500 with catch-up). These limits apply per person across all 401(k) accounts with different employers.
- Priority order: (1) Contribute enough to capture full employer match — this is a 50–100% immediate return, beating any debt payoff rate. (2) Pay off high-interest debt (credit cards, payday loans above 6–7%). (3) Build emergency fund. (4) Max out Roth IRA. (5) Max out 401(k). (6) Pay off lower-interest debt. The exact order depends on your marginal tax rate and debt rates.
- Traditional 401(k): contributions are pre-tax (reduce current taxable income), growth is tax-deferred, withdrawals in retirement are taxed as ordinary income. Roth 401(k): contributions are after-tax (no current deduction), growth is tax-free, qualified withdrawals in retirement are tax-free. If you expect to be in a higher bracket in retirement than today, Roth is better. If you expect lower bracket, traditional is better.
- Excess contributions above the IRS limit must be withdrawn by April 15 of the following year (with earnings). Failure to remove the excess by the deadline results in double taxation — the excess is taxed in the year contributed AND again in the year of distribution. Contact your plan administrator immediately if you notice an over-contribution.