What is a 401k?
A 401(k) is an employer-sponsored retirement savings plan that allows employees to save and invest a portion of their paycheck before taxes are taken out. Taxes are paid when the money is withdrawn in retirement.
2024 401k Contribution Limits
- Employee Contribution: $23,000 (under age 50)
- Catch-up Contribution: Additional $7,500 (age 50+)
- Total Limit (including employer): $69,000 or $76,500 with catch-up
Understanding Employer Matching
Many employers offer matching contributions as an incentive. A common match formula is "50% match up to 6% of salary," which means:
- If you contribute 6% of your salary, your employer adds 3%
- This is essentially free money - always try to get the full match!
- Match formulas vary by employer (some offer 100% match)
Benefits of a 401k
- Tax-Deferred Growth: Your investments grow without being taxed until withdrawal
- Lower Taxable Income: Contributions reduce your current taxable income
- Employer Match: Free money that boosts your savings
- Automatic Saving: Contributions are deducted from your paycheck
- Higher Limits: Contribution limits are higher than IRAs
401k vs Roth 401k
- Traditional 401k: Pre-tax contributions, taxed at withdrawal
- Roth 401k: After-tax contributions, tax-free withdrawals
Tips for Maximizing Your 401k
- At minimum, contribute enough to get the full employer match
- Increase contributions by 1% each year
- Take advantage of catch-up contributions after age 50
- Review and rebalance your investments annually
- Avoid early withdrawals (10% penalty before age 59.5)
Frequently Asked Questions
How accurate are the results?
The 401k applies a standard formula to your inputs — accuracy depends on how precisely you measure those inputs. For planning and estimation, results are reliable. For high-stakes or professional decisions, cross-check the output with a domain expert or primary source.
Does this include Social Security income?
Most retirement calculators focus on portfolio-based savings. Social Security typically provides $1,500–$3,500/month for average earners — add this as an income offset when planning your required portfolio withdrawal rate.
How should I interpret the 401k output?
The result is a calculated estimate based on the formula and your inputs. Compare it against the reference values or benchmarks shown on this page to understand whether your result is high, low, or typical. For decisions with real consequences, use the output as one data point alongside direct measurement and professional advice.
When should I use a different approach?
Use this calculator for quick, formula-based estimates. If your situation involves multiple interacting variables, time-varying inputs, or safety-critical decisions, consider a dedicated software tool, professional consultation, or direct measurement. Calculators are most reliable within their stated assumptions — check that your scenario matches those assumptions before relying on the output.