A Life In Japan

A Life In Japan

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See how your investments could grow.

What happens when you combine a starting amount, monthly contributions and time? Move the sliders and compare your own money with a hypothetical investment value. All amounts are in yen.

Your scenario

The starting values are examples, not suggested investment amounts or expected returns. Change the inputs to explore your own scenario.

Hypothetical value after 20 years

โ€”Before taxes, fees and inflation.
Your total contributions
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Calculated gain / loss
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Your contributions and hypothetical investment growthChange the scenario to compare contributions with calculated investment value.
Scenario valueYour contributions

The gap between the lines is the calculated gain or loss. The yearly table below gives the same information without relying on the graph.

Your yearly numbers

Hypothetical yearly values ยท JPY
YearContributionsScenario valueGain / loss

How this calculation works

Your starting investment is made today. The selected rate is an effective annual return, converted to an equivalent monthly rate. We apply that rate monthly and then add your monthly contribution at the end of the month. Gains stay invested. At 0%, the result is simply the starting amount plus your contributions.

This is a mathematical scenario with a constant return, not a forecast or investment recommendation. Real returns vary and you can lose money. Taxes, fees, inflation, withdrawals and currency changes are excluded. The calculation does not apply NISA rules, limits or eligibility tests.

The calculator does not save or submit your entries.

Start with a budget, then explore the possibilities.

Before choosing an investment amount, understand what your everyday life costs. The monthly budget calculator helps you look at income, bills and the amount you might have available.

Compounding means that previous gains can also generate returns. Regular contributions and time change the scenario, but they do not remove investment risk. For Japan-specific learning, the Financial Services Agency explains asset building, regular investing and diversification through its official resources.

References

Financial Services Agency. (n.d.). The basics of asset building (Japanese).

U.S. Securities and Exchange Commission. (n.d.). Compound Interest Calculator.

Australian Securities and Investments Commission. (n.d.). Compound interest calculator. Moneysmart.

Sources checked 25 October 2026.