Calculators
Japan Salary & Resident Tax Calculator
Simulate income tax, resident tax, social insurance, and take-home pay.
e.g. ¥5M salary → resident tax, take-home, effective tax rate & insurance breakdown
NISA Investment Simulator
Capacity check, peer comparison & 20-year projection
e.g. ¥5M salary → monthly capacity, comfortable range & 20-year projection
Stock & Dollar Rebalance Calculator
Calculate the adjustment needed to reach your target asset allocation.
e.g. $70K stocks / $30K cash (70:30) → how much to buy or sell for 60:40
Financial Knowledge
年収と手取りはどう変わる？所得税をざっくり理解する
2026.06.04 | 所得税・手取り
円安が進むと、家計と資産配分はどこから変わる？
2026.05.26 | 為替・資産配分
New NISA Explained: How to Use Japan's Tax-Free Investment Account
2025.05.21 | Tax-Free Investing
iDeCo Guide: Build Retirement Savings and Reduce Your Tax Bill
2025.05.19 | Retirement Savings
Japan Tax Filing Basics: How to File and Maximize Your Refund
2025.05.18 | Income Tax
Japan Social Insurance Explained: Health, Pension, and Employment
2025.05.18 | Health & Pension
Stock & Cash Rebalancing: How to Keep Your Portfolio on Track
2025.05.16 | Portfolio
FX & Currency Exchange: A Beginner's Guide to Investing in USD
2025.05.12 | FX & Currency
Life Tools