Built for Japan

Your FIRE number,
the Japan way.

Model iDeCo, 新NISA, nenkin, NHI premiums, residence tax, and regional cost of living — all the variables that generic calculators miss.

What makes this different

Japan Tax System

Income tax, residence tax (including the year-1 retirement shock), and NHI premiums that vary with your withdrawal amount.

Nenkin Integration

Model kokumin and kosei nenkin benefits. See how deferring to 70 or 75 changes your FIRE number and break-even age.

iDeCo & 新NISA

Track NISA lifetime caps, model the iDeCo lock-up before 60, and compare tax-advantaged vs taxable withdrawal strategies.

Regional Cost of Living

Tokyo, Osaka, Fukuoka, rural Japan — cost-of-living templates built in. Inaka FIRE is a real strategy worth modeling.

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Monte Carlo Simulation

10,000-path simulations with sequence-of-returns risk. See your p10/p50/p90 outcomes, not just a single projection line.

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Foreign Residents

Non-permanent resident tax rules, totalization agreements, USD/JPY scenario bands, and exit tax warnings for large portfolios.

Japan FIRE — Rules of Thumb

MC Scenario-specific safe rate
Use Monte Carlo to test your withdrawal rate against your own return and volatility assumptions
Year 1 Residence tax shock
You'll pay full residence tax on your last salary in year 1 of retirement. Budget for it.
60歳 iDeCo unlock age
iDeCo is completely illiquid before 60. Pre-60 FIRE means NISA + taxable must cover the gap.
1,800万円 新NISA lifetime cap
1.2M/yr tsumitate + 2.4M/yr growth frame. Tax-free growth and withdrawal, fully liquid.

Ready to run your numbers?

Create a profile, build scenarios, and compare them side by side.

Start calculating