Project your 401k balance at retirement — including employer match and investment growth.
How to Use This 401k Contribution Calculator
Enter your current salary, age, and retirement age, then adjust the sliders for your contribution rate, employer match details, expected investment return, and salary growth. Click "Calculate 401k Projection" to instantly see your estimated balance at retirement, broken down year by year.
All inputs update in real time. Adjust the sliders to explore how small changes — like bumping your contribution from 6% to 10% — can dramatically impact your final balance.
Why This Matters
The 401k is one of the most powerful wealth-building tools available to American workers, yet most people leave significant money on the table. The average American saves just 7% of their paycheck — but even a 2% increase can add hundreds of thousands of dollars over a career.
Consider a 30-year-old earning $75,000 who contributes 8% with a 4% employer match. Over 35 years at a 7% annual return, they could accumulate over $1.4 million — compared to just $900,000 if they only contributed 5%. That's a half-million dollar difference from 3 extra percentage points.
Employer matching is often called "free money" — if your employer matches 100% up to 4% of your salary, you're effectively getting an instant 100% return on that portion. Not capturing the full match is like turning down part of your salary.
This calculator helps employees, new grads, mid-career professionals, and pre-retirees all understand where they stand and what changes to make now.
How It's Calculated
The calculator uses compound growth applied annually. Each year, your salary grows at the salary growth rate, your contributions are calculated, the employer match is applied (capped at the match limit), and investment gains are earned on the running balance.
Annual Employee Contribution = Salary × Contribution Rate
Annual Employer Match = Salary × MIN(Contribution Rate, Match Cap) × Match Rate
Investment Gain = (Beginning Balance + Contributions) × Annual Return Rate
Year-End Balance = Beginning Balance + Employee Contribution + Employer Match + Investment Gain
The IRS limits 401k contributions to $23,000 in 2024 (employees under 50). The calculator applies this limit automatically. Salary grows by your chosen growth rate each year, meaning contributions also grow over time.
Tips & Common Mistakes
- Always capture the full employer match. If your employer matches 100% up to 4%, contribute at least 4%. Anything less is turning down free compensation.
- Don't assume 10% returns. While the S&P 500 has historically averaged ~10% nominal, 6–7% real returns (after inflation) is a more conservative and realistic assumption for long-term planning.
- Increase contributions at every raise. When you get a 3% raise, redirect 1–2% of it to your 401k. You'll barely notice the take-home difference, but the compounding impact is massive.
- Check your vesting schedule. Employer match funds may not be fully yours for 2–6 years. If you leave early, you could forfeit some matched funds.
- Don't stop contributing during market downturns. Dropping contributions when markets fall means you miss out on buying more shares at lower prices — exactly when you should be buying more.
Frequently Asked Questions
What is the 2024 401k contribution limit?
For 2024, employees can contribute up to $23,000 to their 401k. If you are 50 or older, you can make an additional "catch-up" contribution of $7,500, bringing the total to $30,500. This calculator automatically caps contributions at the $23,000 limit.
Does my employer match count toward the IRS limit?
No — employer contributions do not count against your personal $23,000 limit. However, the combined employee + employer total cannot exceed $69,000 (in 2024). For most people, the personal contribution limit is the relevant cap.
What's a realistic expected annual return for my 401k?
A common assumption for a diversified equity-heavy portfolio is 6–8% per year. The S&P 500 has historically returned about 10% nominally, but accounting for inflation and fees, 6–7% is a more conservative and widely used planning figure. More bond-heavy portfolios might use 4–5%.
What happens if I change jobs?
If you change jobs, you can roll your 401k balance into your new employer's 401k plan or into an IRA — both without tax penalties if done correctly as a direct rollover. Cashing out early results in income taxes plus a 10% penalty, which can erode a huge portion of your savings.