{
  "$comment": "Machine-readable companion to https://valem.run/calculators/japan/net-salary. Formula, inputs, outputs, engine-verified test vectors, cited sources and the re-runnable Valem ModelSpec behind the page.",
  "url": "https://valem.run/calculators/japan/net-salary",
  "dataUrl": "https://valem.run/calculators/japan/net-salary.json",
  "license": {
    "name": "CC BY 4.0",
    "url": "https://creativecommons.org/licenses/by/4.0/",
    "attribution": "Japan take-home pay model by Valem (https://valem.run/calculators/japan/net-salary), CC BY 4.0.",
    "note": "Covers the model — the expression of each rule and the arrangement of the catalog. The rates and thresholds themselves are law and are not licensed by anyone; the cited sources are where they come from."
  },
  "verificationUrl": "https://valem.run/calculators/japan/net-salary/verify",
  "country": "japan",
  "countryName": "Japan",
  "formula": "net-salary",
  "formulaName": "Take-home pay",
  "title": "手取り計算 — Japan net salary",
  "answer": "Your Japanese take-home is gross minus about 14.69% social insurance, national income tax and a 10% resident tax.",
  "lang": "en",
  "currency": "JPY",
  "taxYear": "2026",
  "verification": {
    "claim": "internal-consistency",
    "statement": "The Valem engine reproduces this model's stated formula through 2 self-test cases (below, and re-runnable against the spec). That asserts internal consistency, NOT that the formula matches current law — the cited sources are the evidence for that, and carry the date each was last checked.",
    "selfTestCases": 2,
    "ratesAreIllustrative": false,
    "sourcesCheckedOn": "2026-08-02"
  },
  "sources": [
    {
      "label": "国税庁 (NTA)",
      "url": "https://www.nta.go.jp",
      "checked": "2026-08-02"
    }
  ],
  "terminalOutput": "netMonthly",
  "inputs": [
    {
      "name": "grossAnnual",
      "type": "number",
      "label": "年収 (JPY)",
      "format": "currency",
      "minimum": 0
    }
  ],
  "outputs": [
    {
      "name": "social",
      "type": "number",
      "label": "社会保険 (~14.66%)",
      "format": "currency",
      "formula": "$round(grossAnnual * $const.socialRate, 2)"
    },
    {
      "name": "taxable",
      "type": "number",
      "formula": "($b := grossAnnual - social - $const.deduction; $round($b > 0 ? $b : 0, 2))"
    },
    {
      "name": "nationalTax",
      "type": "number",
      "label": "所得税",
      "format": "currency",
      "formula": "($t := taxable; $round((($t < 1950000 ? $t : 1950000) * 0.05) + (($t > 1950000 ? (($t < 3300000 ? $t : 3300000) - 1950000) : 0) * 0.10) + (($t > 3300000 ? (($t < 6950000 ? $t : 6950000) - 3300000) : 0) * 0.20) + (($t > 6950000 ? (($t < 9000000 ? $t : 9000000) - 6950000) : 0) * 0.23) + (($t > 9000000 ? (($t < 18000000 ? $t : 18000000) - 9000000) : 0) * 0.33) + (($t > 18000000 ? ($t - 18000000) : 0) * 0.40), 2))"
    },
    {
      "name": "residentTax",
      "type": "number",
      "label": "住民税 (10%)",
      "format": "currency",
      "formula": "$round(taxable * $const.residentRate, 2)"
    },
    {
      "name": "netAnnual",
      "type": "number",
      "label": "手取り / 年",
      "format": "currency",
      "formula": "$round(grossAnnual - social - nationalTax - residentTax, 2)"
    },
    {
      "name": "netMonthly",
      "type": "number",
      "label": "手取り / 月",
      "format": "currency",
      "formula": "$round(netAnnual / 12, 2)"
    }
  ],
  "testCases": [
    {
      "description": "S1 5,000,000 JPY",
      "given": {
        "grossAnnual": 5000000
      },
      "expect": {
        "social": 734500
      }
    },
    {
      "description": "S2 7,000,000 JPY",
      "given": {
        "grossAnnual": 7000000
      },
      "expect": {
        "social": 1028300
      }
    }
  ],
  "spec": {
    "id": "net-salary-japan",
    "version": "1.0.0",
    "schema": {
      "type": "object",
      "properties": {
        "grossAnnual": {
          "type": "number",
          "minimum": 0
        },
        "social": {
          "type": "number",
          "readOnly": true
        },
        "taxable": {
          "type": "number",
          "readOnly": true
        },
        "nationalTax": {
          "type": "number",
          "readOnly": true
        },
        "residentTax": {
          "type": "number",
          "readOnly": true
        },
        "netAnnual": {
          "type": "number",
          "readOnly": true
        },
        "netMonthly": {
          "type": "number",
          "readOnly": true
        }
      }
    },
    "constants": {
      "socialRate": 0.1469,
      "deduction": 1000000,
      "residentRate": 0.1
    },
    "defaultValues": [
      {
        "path": "$",
        "expr": "{ 'grossAnnual': 5000000 }"
      }
    ],
    "derivations": [
      {
        "path": "$.social",
        "expr": "$round(grossAnnual * $const.socialRate, 2)"
      },
      {
        "path": "$.taxable",
        "expr": "($b := grossAnnual - social - $const.deduction; $round($b > 0 ? $b : 0, 2))"
      },
      {
        "path": "$.nationalTax",
        "expr": "($t := taxable; $round((($t < 1950000 ? $t : 1950000) * 0.05) + (($t > 1950000 ? (($t < 3300000 ? $t : 3300000) - 1950000) : 0) * 0.10) + (($t > 3300000 ? (($t < 6950000 ? $t : 6950000) - 3300000) : 0) * 0.20) + (($t > 6950000 ? (($t < 9000000 ? $t : 9000000) - 6950000) : 0) * 0.23) + (($t > 9000000 ? (($t < 18000000 ? $t : 18000000) - 9000000) : 0) * 0.33) + (($t > 18000000 ? ($t - 18000000) : 0) * 0.40), 2))"
      },
      {
        "path": "$.residentTax",
        "expr": "$round(taxable * $const.residentRate, 2)"
      },
      {
        "path": "$.netAnnual",
        "expr": "$round(grossAnnual - social - nationalTax - residentTax, 2)"
      },
      {
        "path": "$.netMonthly",
        "expr": "$round(netAnnual / 12, 2)"
      }
    ],
    "constraints": [],
    "metaDerivations": [],
    "viewDefinition": {
      "renderer": "builtin",
      "defaultView": "main",
      "views": [
        {
          "id": "main",
          "label": "手取り",
          "layout": "vertical",
          "components": [
            {
              "id": "gross",
              "type": "numericField",
              "label": "年収 (JPY)",
              "bind": "$.grossAnnual"
            },
            {
              "id": "tiles",
              "type": "group",
              "layout": "horizontal",
              "components": [
                {
                  "id": "netM",
                  "type": "statTile",
                  "label": "手取り / 月",
                  "bind": "$.netMonthly",
                  "format": "currency",
                  "currency": "JPY"
                },
                {
                  "id": "netY",
                  "type": "statTile",
                  "label": "手取り / 年",
                  "bind": "$.netAnnual",
                  "format": "currency",
                  "currency": "JPY"
                }
              ]
            },
            {
              "id": "breakdown",
              "type": "keyValueList",
              "label": "内訳",
              "items": [
                {
                  "label": "額面",
                  "bind": "$.grossAnnual",
                  "format": "currency",
                  "currency": "JPY"
                },
                {
                  "label": "社会保険 (~14.66%)",
                  "bind": "$.social",
                  "format": "currency",
                  "currency": "JPY"
                },
                {
                  "label": "所得税",
                  "bind": "$.nationalTax",
                  "format": "currency",
                  "currency": "JPY"
                },
                {
                  "label": "住民税 (10%)",
                  "bind": "$.residentTax",
                  "format": "currency",
                  "currency": "JPY"
                },
                {
                  "label": "手取り",
                  "bind": "$.netAnnual",
                  "format": "currency",
                  "currency": "JPY"
                }
              ]
            },
            {
              "id": "note",
              "type": "staticText",
              "text": "'日本 2026年度 (簡略): 社会保険 約14.69% (厚生年金9.15% + 健康保険4.925%〔東京・協会けんぽ〕 + 雇用保険0.5% + 2026年4月開始の子ども・子育て支援金0.115%)、所得税 5-45%、住民税 10%。給与所得控除・基礎控除は簡略化。概算であり税務助言ではありません。'"
            },
            {
              "id": "sources",
              "type": "sourceList",
              "label": "出典",
              "items": [
                {
                  "label": "国税庁 (NTA)",
                  "url": "https://www.nta.go.jp",
                  "date": "2026-08-02"
                }
              ]
            }
          ]
        }
      ]
    },
    "tests": [
      {
        "description": "S1 5,000,000 JPY",
        "given": {
          "$.grossAnnual": 5000000
        },
        "expect": {
          "$.social": 734500
        }
      },
      {
        "description": "S2 7,000,000 JPY",
        "given": {
          "$.grossAnnual": 7000000
        },
        "expect": {
          "$.social": 1028300
        }
      }
    ]
  }
}