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Free Japanese Tax & Finance Calculators

For foreign residents in Japan and anyone needing to calculate Japanese income tax, pension, residence tax, mortgage, NHI, and 1,000+ other daily-life numbers. All free, no signup, in your browser only.

📅 2026 tax-year ready🔒 Privacy: data stays on your device📍 Source: NTA / MHLW / Tokyo Metropolis

Top 20 calculators for residents in Japan

The Japanese-language form is the source of truth for now; an English UI is in progress. The link below opens the Japanese page — most fields use international numbers and the result is universal.

tax

Japanese Income Tax Calculator

Free calculator for Japan income tax — works for residents, foreign workers, and freelancers. 2026 tax-year rates, including 復興特別所得税 (reconstruction surtax).

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tax

Japanese Residence Tax Calculator

Free calculator for Japan residence tax. Approx 10% flat on taxable income, billed by your municipality from June.

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tax

Japan Take-Home Pay Calculator

See your real Japanese take-home salary after income tax, residence tax, health insurance, pension, and employment insurance.

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insurance

NHI (国民健康保険) Calculator

Japanese NHI premium calculator. Required if you're self-employed, freelancing, or unemployed. Varies by city.

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pension

National Pension (国民年金) Calculator

Calculate your monthly Kokumin Nenkin contribution and estimated pension at age 65.

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mortgage

Japan Mortgage Monthly Payment

Japanese mortgage calculator: monthly payment, total interest, and principal breakdown for housing loans in Japan.

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tax

Furusato Nozei (Hometown Tax) Limit

Furusato Nozei donation cap calculator. Donate to Japanese cities, get gifts, and reduce your taxes — only ¥2,000 net cost.

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investment

iDeCo Tax Saving Calculator

iDeCo Japan calculator: annual tax savings on contributions. Foreigners with permanent residence eligible.

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investment

New NISA Simulation (2024+)

New NISA (2024+) tax-free investment simulator. Up to ¥18 million lifetime, no tax on gains or dividends.

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tax

Japanese Inheritance Tax (相続税)

Japanese inheritance tax calculator. Basic deduction = ¥30M + ¥6M × heirs. Spouse exemption up to ¥160M.

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tax

Gift Tax (贈与税) Calculator

Japanese gift tax (Zōyozei) calculator. Annual ¥1.1M exemption, with progressive rates above.

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pension

Pension Estimator (Kokumin + Kosei)

Calculate your Japanese pension at retirement: kokumin nenkin + kosei nenkin combined.

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tax

Retirement Allowance Tax

Japanese retirement allowance (taishokukin) tax calculator. Generous deduction for years of service.

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tax

Consumption Tax (消費税)

Japanese consumption tax calculator. 10% standard, 8% on food/beverages (eat-out 10%).

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tax

Property Tax (固定資産税)

Japanese property tax calculator (Kotei Shisanzei + Toshi Keikaku Zei). Annual tax for property owners.

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tax

Real Estate Acquisition Tax

Japan property purchase tax calculator. 3% (residential) or 4% (non-residential) of assessed value.

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tax

Crypto Tax (仮想通貨)

Japan cryptocurrency tax calculator. Treated as miscellaneous income — combined with salary, up to 55% top rate.

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tax

Freelance Rate Calculator

Japan freelance rate calculator. Reverse-engineer required revenue from target income, accounting for tax + NHI + pension.

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health

BMI Calculator

Quick BMI calculator with WHO and Japanese categories.

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health

Daily Calorie Needs

Calculate daily calorie requirements using Mifflin-St Jeor formula. Includes weight loss/gain targets.

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health

Pregnancy Due Date

Japanese-style pregnancy due date calculator. Based on standard 280-day gestation.

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life

Affordable Rent in Japan

How much rent can you afford in Japan? Conservative / standard / max guideline based on monthly take-home.

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life

Moving Cost in Japan

Japan moving cost calculator. Estimate by belongings volume + distance + season.

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life

Age Calculator (Japanese-style)

Age calculator showing years/months/days, days since birth, and days until next birthday. Includes Eto (Chinese zodiac).

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life

Days Between Two Dates

Calculate the precise difference between two dates in days, weeks, months, and approximate years.

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mortgage

Japanese Mortgage Loan Comparison Calculator

Compare 2 Japanese mortgage offers: monthly payment, total interest, lifetime cost. Supports 元利均等返済 (equal-payment) repayment.

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tax

Japanese Overtime Pay Calculator

Free calculator for Japanese overtime pay: 25% weekday, 50% over 60h/month, 25% late-night (22:00–05:00), 35% holiday — based on the Labor Standards Act.

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unit

Tsubo ↔ Square Meter Converter (Japanese Floor Area)

Convert 坪 (tsubo) to m² or m² to tsubo. 1 tsubo = 3.3058 m² ≈ 2 tatami mats. Used for Japanese apartments, houses, and land listings.

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Looking for a specific calculator that isn't listed? Browse all 1,000+ tools or use the search box at the top right.

Why Keisan Tools?

  • No signup, no loginEverything runs in your browser. Favorites and history are stored locally — never on a server.
  • 2026 tax-year compliantUpdated for the latest NTA brackets, NHI rates, and pension contribution amounts.
  • Designed for residents in JapanMost online calculators in English are US/UK biased. Ours follows Japanese rules end-to-end.
  • Mobile-first designOptimized for any device — phone, tablet, or desktop. Voice input available on supported tools.

⚠️ Disclaimer: These calculators are estimates. For actual tax filing, please consult a licensed 税理士 (zeirishi) or FP (financial planner). Results are not a substitute for professional advice.