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Take-home Pay Simulator

Base salary + allowances. Commuting allowance goes below
Ages 40–64 pay nursing-care insurance
As declared on the dependents declaration form

About this calculation

Take-home pay is gross salary minus social insurance (health, nursing, employees' pension, employment insurance), withheld income tax and resident tax. For employees these are deducted at source, so net pay is typically 20–30% below gross.

How it is calculated

  1. Compute the standard monthly remuneration, then the employee share of health insurance (Kyokai Kenpo, per-prefecture rate; nursing added from age 40) and employees' pension (18.3%, split with employer).
  2. Apply the employment-insurance rate (employee share) to gross pay.
  3. Apply the withholding tax table (monthly table, kou/otsu column, dependants) to pay after social insurance to get withheld income tax.
  4. Subtract resident tax (special collection based on prior-year income); the remainder is take-home pay.

Statutory basis (e-Gov)

  • 健康保険法 第160条 — Kyokai Kenpo premium rate (per prefecture) e-Gov last amended 2026-06-05
  • 厚生年金保険法 第81条 — Employees' pension premium rate (18.3%) e-Gov last amended 2024-06-14
  • 所得税法 第185条 — Withholding tax on salary (monthly table) e-Gov last amended 2026-07-23
  • 労働保険の保険料の徴収等に関する法律 第12条 — Employment insurance rate e-Gov last amended 2024-05-17

Frequently asked questions

Why is the gap between gross and net so large?

Social insurance (employees' pension alone is 9.15% on the employee side) plus income and resident tax are withheld. The gap varies with income, dependants and prefecture (health-insurance rate).

Why is resident tax not deducted in the first year of employment?

Resident tax is levied on prior-year income from the following June, so with no prior-year income nothing is withheld in year one. This tool assumes prior-year income equals this year's salary.

What determines the health-insurance rate?

For Kyokai Kenpo the rate is set per prefecture and revised each fiscal year (Health Insurance Act, Art. 160). This tool uses the FY2026 (Reiwa 8) prefectural rates.

Published by: 心享勢成株式会社（SEISEI INC.） · Last updated: 2026-09-12 · Tax year: 令和8年度（2026年度） · About the publisher

本ツールは一般的な税制情報に基づく概算シミュレーションです。個別の税額計算・申告・税務相談は提携税理士が承ります。算出結果は法的助言ではなく、参考値としてご利用ください。