Investment ROI Calculator
Calculate total return, percentage gain, and annualized CAGR from any investment.
CAGR Reference — Doubling Time
| Annual Return | Years to Double | $10k after 20 years |
|---|---|---|
| 4% | 18.0 years | $21,911 |
| 6% | 12.0 years | $32,071 |
| 7% | 10.3 years | $38,697 |
| 10% | 7.2 years | $67,275 |
| 12% | 6.0 years | $96,463 |
Frequently Asked Questions
How do I calculate ROI?
ROI (Return on Investment) = (Final Value − Initial Investment) / Initial Investment × 100%. Example: invest $10,000, value grows to $14,500. ROI = ($14,500 − $10,000) / $10,000 × 100% = 45%. ROI does not account for the time period — a 45% return over 3 years is very different from 45% over 10 years.
What is CAGR (Compound Annual Growth Rate)?
CAGR is the annualized rate of return that would produce the same final value over the holding period, assuming compound growth. Formula: CAGR = (Final Value / Initial Value)^(1/Years) − 1. Example: $10,000 grows to $18,500 over 5 years. CAGR = ($18,500/$10,000)^(1/5) − 1 = 13.1%/year. CAGR allows fair comparison of investments held for different time periods.
What is a good ROI for an investment?
Context matters greatly. S&P 500 historical CAGR: ~10% annually before inflation, ~7% after inflation. A 7% CAGR doubles your money in ~10 years (rule of 72). Real estate averages 3–5% annually in appreciation (plus rental income). Individual stocks vary widely. A CAGR above the S&P 500 average is considered above-market performance.
What is the Rule of 72?
The Rule of 72 is a quick estimate of how many years it takes to double your money: Years to double = 72 / Annual Return %. At 7% return: 72/7 ≈ 10.3 years. At 10% return: 72/10 = 7.2 years. At 4% return: 72/4 = 18 years. It is an approximation — the exact answer requires using the CAGR formula.
How do taxes affect investment returns?
After-tax returns are lower than reported returns. Long-term capital gains (assets held >1 year) are taxed at 0%, 15%, or 20% depending on income. Short-term gains are taxed at ordinary income rates (10–37%). A 10% pre-tax return becomes roughly 8–8.5% after a 15% capital gains rate. Tax-advantaged accounts (401k, IRA, HSA) shield growth from annual taxation.