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Investment Calculator
Future Value
Total Earnings: $153,018
Investing: Start Now, Thank Yourself Later
$500/month at 7% for 30 years = $612k. That's not a typo. You put in $180k, compound interest did the other $432k. This is why people tell you to start early.
💡 Real Talk from David Chen, CFA
Most people overthink this. Buy a low-cost S&P 500 index fund (like VOO or SPY). Add money every month. Don't check it daily. That's it. You'll beat 90% of active fund managers who charge 10x the fees.
Real Examples
$200/month for 10 years at 8%: You put in $24k, it grows to $36.6k. Free $12.6k.
$500/month for 20 years at 7%: You put in $120k, it grows to $261k. Free $141k.
$1000/month for 30 years at 10%: You put in $360k, it grows to $2.3M. Retire early.
⚠️ Common Mistake: Selling During Crashes
Market drops 30%? Congrats, stocks are on sale. Keep buying. Selling when it's down locks in your losses. Every crash in history recovered. 2008, 2020, all of them. People who held won. People who panicked lost.
What Return Rate Should You Use?
- Conservative (5-6%): Bonds, dividend stocks. Safer, lower returns.
- Moderate (7-8%): Mixed portfolio. 60% stocks, 40% bonds.
- Aggressive (10%+): All stocks, long-term. S&P 500 averaged 10.26% since 1957.
Don't assume 15% just because some year hit that. Use 7-8% to be realistic.
Index Funds vs Stock Picking
You're not Warren Buffett. You don't have time to research 50 companies. Just buy the whole market via index fund. It's boring, but it works.
Popular index funds:
- VOO (Vanguard S&P 500) - 0.03% fee
- VTI (Total US Market) - 0.03% fee
- VXUS (International) - 0.07% fee
Compare that to actively managed funds charging 1-2% fees. That difference compounds over decades.
Tax-Advantaged Accounts First
Before using a regular brokerage account, max out:
- 401k match - Free money from employer
- Roth IRA - $7k/year (2025), grows tax-free forever
- HSA - If you have high-deductible plan, triple tax advantage
- Rest of 401k - Up to $2k limit
Only then use a taxable brokerage. Tax savings compound too.
The Hardest Part: Doing Nothing
Set up automatic investing. $500 leaves your account every month, goes straight to VOO. Then forget about it for a year.
Checking your portfolio daily makes you sell when it drops. That's how you lose. Time in the market beats timing the market.
Reviewed by David Chen, CFA
Chartered Financial Analyst
David helps people invest consistently without freaking out during market drops.
Frequently Asked Questions
Is $500 a month enough to invest?
Absolutely. $500/month at 7% for 30 years = $612k. You contributed $180k, compound interest gave you $432k. Start with whatever you can—$100, $50, even $25. Consistency matters more than the amount.
What's a realistic return rate for investments?
S&P 500 has averaged ~10% annually since 1957. But use 7-8% to be safe—some years are down 20%, others up 30%. Over decades it evens out. Don't assume you'll beat the market. You probably won't.
Should I invest if I have debt?
Depends on interest rate. Credit card at 18%? Pay that off first. Student loans at 4%? You can invest while paying it. Get any 401k match though—that's free money.