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Inputs are calculated in your browser and are not sent to a server. When you use sharing, the reproducible URL includes the current conditions.
Money
Compound Interest Calculator
Estimate future value and gains from principal, monthly contribution, annual rate, and term.
Updated: May 15, 2026
Input
Estimate future value and gains from principal, monthly contribution, annual rate, and term.
Simple estimate only. Taxes, fees, inflation, and price changes are excluded. Not investment advice and not a guaranteed return.
Result
¥6,305,478
Future value
¥4,600,000
Principal total
¥1,705,478
Estimated gain
120
Months
Use this as a guide and adjust for your real conditions.
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How to use
- Enter Principal, Monthly contribution, Annual rate, Years.
- Check the estimate in the result area.
- Share a reproducible URL if needed.
How to read the result
- Read Future value, Principal total, Estimated gains as quick decision-making estimates.
- Do not treat the result as a fixed answer; adjust assumptions to see the range when needed.
Useful tips
- Useful when you want to estimate future value with monthly investing; adjust inputs to compare scenarios.
- Useful when you want to compare rough annual return assumptions; adjust inputs to compare scenarios.
- Change one input at a time to see how payment, shortfall, or cost moves.
- Use values close to the real quote, bill, or checkout screen.
Calculation
Estimates future value from principal, monthly contribution, annual return, duration, and compounding frequency. Taxes, fees, and market movement are not included.
Notes
- Use results as a guide.
- This is not tax, labor, or financial advice.
- Actual deductions and conditions can differ.
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FAQ
Are results exact?
Use results as everyday estimates. For exact decisions, confirm with official or specialized sources.
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