Opportunity Cost Calculator
Every choice has an opportunity cost — the return of the best alternative you pass up. Compare two options over time to see which comes out ahead and by how much.
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Learn moreWhy opportunity cost matters
Opportunity cost is what you forgo by choosing one option over the next-best one. Leaving $10,000 in a 2% account instead of a diversified portfolio earning ~8% isn’t “free” — over years, the gap compounds into a large sum. Thinking in opportunity cost turns “I’m not losing money” into “what am I giving up?”
How it’s calculated & sources
Each option grows at its annual return: amount × (1 + rate)^years. Opportunity cost = the difference in ending values — the gain you forgo by not choosing the higher-returning option.
Benchmark: a common reference alternative is the stock market’s ~10%/yr long-run average; cash and savings return far less.
Results update as you type and are general estimates, not personalized advice. Verify with a professional.
Worked example
$10,000 at 2% for 10 years grows to about $12,190; at 8% it grows to about $21,590 — an opportunity cost of roughly $9,400 for playing it safe.
Frequently asked questions
Is opportunity cost real money?
It’s not cash out of pocket, but it is real forgone growth — money you could have had by choosing the better option.
What return should I use for the alternative?
Use a realistic rate for a comparable-risk option — e.g., ~8–10% for a diversified stock portfolio over the long run.
Does it account for risk?
No — higher returns usually carry more risk. Weigh the opportunity cost against how much volatility you can tolerate.