{
  "$comment": "Machine-readable companion to https://valem.run/calculators/uk/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/uk/net-salary",
  "dataUrl": "https://valem.run/calculators/uk/net-salary.json",
  "license": {
    "name": "CC BY 4.0",
    "url": "https://creativecommons.org/licenses/by/4.0/",
    "attribution": "United Kingdom take-home pay model by Valem (https://valem.run/calculators/uk/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/uk/net-salary/verify",
  "country": "uk",
  "countryName": "United Kingdom",
  "formula": "net-salary",
  "formulaName": "Take-home pay",
  "title": "Take Home Pay Calculator UK 2025-26 — net salary",
  "answer": "Your UK take-home pay is your gross minus income tax (after the personal allowance) and employee National Insurance, plus any pension contribution you make.",
  "lang": "en",
  "currency": "GBP",
  "taxYear": "2025-26",
  "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": "GOV.UK — Income Tax rates and allowances",
      "url": "https://www.gov.uk/income-tax-rates",
      "checked": "2026-08-02"
    },
    {
      "label": "GOV.UK — NI rates & thresholds 2025-26",
      "url": "https://www.gov.uk/guidance/rates-and-thresholds-for-employers-2025-to-2026",
      "checked": "2026-08-02"
    }
  ],
  "terminalOutput": "netMonthly",
  "inputs": [
    {
      "name": "grossAnnual",
      "type": "number",
      "label": "Gross annual salary (GBP)",
      "format": "currency",
      "minimum": 0
    },
    {
      "name": "pensionPct",
      "type": "number",
      "label": "Pension contribution (fraction, e.g. 0.05)",
      "minimum": 0,
      "maximum": 1
    }
  ],
  "outputs": [
    {
      "name": "pensionContribution",
      "type": "number",
      "formula": "$round(grossAnnual * pensionPct, 2)"
    },
    {
      "name": "adjustedIncome",
      "type": "number",
      "formula": "$round(grossAnnual - pensionContribution, 2)"
    },
    {
      "name": "personalAllowance",
      "type": "number",
      "label": "Personal allowance",
      "format": "currency",
      "formula": "($over := adjustedIncome - $const.paTaperThreshold; $red := $over > 0 ? $over / 2 : 0; $pa := $const.paBase - $red; $round($pa > 0 ? $pa : 0, 2))"
    },
    {
      "name": "taxableIncome",
      "type": "number",
      "label": "Taxable income",
      "format": "currency",
      "formula": "($ti := adjustedIncome - personalAllowance; $round($ti > 0 ? $ti : 0, 2))"
    },
    {
      "name": "incomeTax",
      "type": "number",
      "label": "Income tax",
      "format": "currency",
      "formula": "($ti := taxableIncome; $b := $ti < $const.basicBand ? $ti : $const.basicBand; $h := $ti > $const.basicBand ? ($ti < $const.higherTaxableLimit ? $ti : $const.higherTaxableLimit) - $const.basicBand : 0; $a := $ti > $const.higherTaxableLimit ? $ti - $const.higherTaxableLimit : 0; $round($b * $const.basicRate + $h * $const.higherRate + $a * $const.additionalRate, 2))"
    },
    {
      "name": "ni",
      "type": "number",
      "label": "National Insurance",
      "format": "currency",
      "formula": "($m := (grossAnnual < $const.niUpperLimit ? grossAnnual : $const.niUpperLimit) - $const.niPrimaryThreshold; $m := $m > 0 ? $m : 0; $u := grossAnnual - $const.niUpperLimit; $u := $u > 0 ? $u : 0; $round($m * $const.niMainRate + $u * $const.niUpperRate, 2))"
    },
    {
      "name": "netAnnual",
      "type": "number",
      "label": "Net / year",
      "format": "currency",
      "formula": "$round(grossAnnual - pensionContribution - incomeTax - ni, 2)"
    },
    {
      "name": "netMonthly",
      "type": "number",
      "label": "Net / month",
      "format": "currency",
      "formula": "$round(netAnnual / 12, 2)"
    }
  ],
  "testCases": [
    {
      "description": "S1 35,000 GBP single, no pension",
      "given": {
        "grossAnnual": 35000,
        "pensionPct": 0
      },
      "expect": {
        "personalAllowance": 12570,
        "taxableIncome": 22430,
        "incomeTax": 4486,
        "ni": 1794.4,
        "netAnnual": 28719.6,
        "netMonthly": 2393.3
      }
    },
    {
      "description": "S3 130,000 GBP — personal allowance fully tapered",
      "given": {
        "grossAnnual": 130000,
        "pensionPct": 0
      },
      "expect": {
        "personalAllowance": 0,
        "taxableIncome": 130000
      }
    }
  ],
  "spec": {
    "id": "net-salary-uk",
    "version": "1.0.0",
    "schema": {
      "type": "object",
      "properties": {
        "grossAnnual": {
          "type": "number",
          "minimum": 0
        },
        "pensionPct": {
          "type": "number",
          "minimum": 0,
          "maximum": 1
        },
        "pensionContribution": {
          "type": "number",
          "readOnly": true
        },
        "adjustedIncome": {
          "type": "number",
          "readOnly": true
        },
        "personalAllowance": {
          "type": "number",
          "readOnly": true
        },
        "taxableIncome": {
          "type": "number",
          "readOnly": true
        },
        "incomeTax": {
          "type": "number",
          "readOnly": true
        },
        "ni": {
          "type": "number",
          "readOnly": true
        },
        "netAnnual": {
          "type": "number",
          "readOnly": true
        },
        "netMonthly": {
          "type": "number",
          "readOnly": true
        }
      }
    },
    "constants": {
      "paBase": 12570,
      "paTaperThreshold": 100000,
      "basicBand": 37700,
      "higherTaxableLimit": 112570,
      "basicRate": 0.2,
      "higherRate": 0.4,
      "additionalRate": 0.45,
      "niPrimaryThreshold": 12570,
      "niUpperLimit": 50270,
      "niMainRate": 0.08,
      "niUpperRate": 0.02
    },
    "defaultValues": [
      {
        "path": "$",
        "expr": "{ 'grossAnnual': 35000, 'pensionPct': 0 }"
      }
    ],
    "derivations": [
      {
        "path": "$.pensionContribution",
        "expr": "$round(grossAnnual * pensionPct, 2)"
      },
      {
        "path": "$.adjustedIncome",
        "expr": "$round(grossAnnual - pensionContribution, 2)"
      },
      {
        "path": "$.personalAllowance",
        "expr": "($over := adjustedIncome - $const.paTaperThreshold; $red := $over > 0 ? $over / 2 : 0; $pa := $const.paBase - $red; $round($pa > 0 ? $pa : 0, 2))"
      },
      {
        "path": "$.taxableIncome",
        "expr": "($ti := adjustedIncome - personalAllowance; $round($ti > 0 ? $ti : 0, 2))"
      },
      {
        "path": "$.incomeTax",
        "expr": "($ti := taxableIncome; $b := $ti < $const.basicBand ? $ti : $const.basicBand; $h := $ti > $const.basicBand ? ($ti < $const.higherTaxableLimit ? $ti : $const.higherTaxableLimit) - $const.basicBand : 0; $a := $ti > $const.higherTaxableLimit ? $ti - $const.higherTaxableLimit : 0; $round($b * $const.basicRate + $h * $const.higherRate + $a * $const.additionalRate, 2))"
      },
      {
        "path": "$.ni",
        "expr": "($m := (grossAnnual < $const.niUpperLimit ? grossAnnual : $const.niUpperLimit) - $const.niPrimaryThreshold; $m := $m > 0 ? $m : 0; $u := grossAnnual - $const.niUpperLimit; $u := $u > 0 ? $u : 0; $round($m * $const.niMainRate + $u * $const.niUpperRate, 2))"
      },
      {
        "path": "$.netAnnual",
        "expr": "$round(grossAnnual - pensionContribution - incomeTax - ni, 2)"
      },
      {
        "path": "$.netMonthly",
        "expr": "$round(netAnnual / 12, 2)"
      }
    ],
    "constraints": [],
    "metaDerivations": [],
    "viewDefinition": {
      "renderer": "builtin",
      "defaultView": "main",
      "views": [
        {
          "id": "main",
          "label": "Take-home pay",
          "layout": "vertical",
          "components": [
            {
              "id": "gross",
              "type": "numericField",
              "label": "Gross annual salary (GBP)",
              "bind": "$.grossAnnual"
            },
            {
              "id": "pension",
              "type": "numericField",
              "label": "Pension contribution (fraction, e.g. 0.05)",
              "bind": "$.pensionPct"
            },
            {
              "id": "tiles",
              "type": "group",
              "layout": "horizontal",
              "components": [
                {
                  "id": "netM",
                  "type": "statTile",
                  "label": "Net / month",
                  "bind": "$.netMonthly",
                  "format": "currency",
                  "currency": "GBP"
                },
                {
                  "id": "netY",
                  "type": "statTile",
                  "label": "Net / year",
                  "bind": "$.netAnnual",
                  "format": "currency",
                  "currency": "GBP"
                }
              ]
            },
            {
              "id": "sep1",
              "type": "separatorLine"
            },
            {
              "id": "breakdown",
              "type": "keyValueList",
              "label": "Annual breakdown",
              "items": [
                {
                  "label": "Gross",
                  "bind": "$.grossAnnual",
                  "format": "currency",
                  "currency": "GBP"
                },
                {
                  "label": "Personal allowance",
                  "bind": "$.personalAllowance",
                  "format": "currency",
                  "currency": "GBP"
                },
                {
                  "label": "Taxable income",
                  "bind": "$.taxableIncome",
                  "format": "currency",
                  "currency": "GBP"
                },
                {
                  "label": "Income tax",
                  "bind": "$.incomeTax",
                  "format": "currency",
                  "currency": "GBP"
                },
                {
                  "label": "National Insurance",
                  "bind": "$.ni",
                  "format": "currency",
                  "currency": "GBP"
                },
                {
                  "label": "Net pay",
                  "bind": "$.netAnnual",
                  "format": "currency",
                  "currency": "GBP"
                }
              ]
            },
            {
              "id": "note",
              "type": "staticText",
              "text": "'UK 2025-26 (rest of UK): personal allowance £12,570 tapered above £100,000, income tax 20/40/45%, employee NI 8% then 2%. Estimate, not tax advice.'"
            },
            {
              "id": "sources",
              "type": "sourceList",
              "label": "Sources",
              "items": [
                {
                  "label": "GOV.UK — Income Tax rates and allowances",
                  "url": "https://www.gov.uk/income-tax-rates",
                  "date": "2026-08-02"
                },
                {
                  "label": "GOV.UK — NI rates & thresholds 2025-26",
                  "url": "https://www.gov.uk/guidance/rates-and-thresholds-for-employers-2025-to-2026",
                  "date": "2026-08-02"
                }
              ]
            }
          ]
        }
      ]
    },
    "tests": [
      {
        "description": "S1 35,000 GBP single, no pension",
        "given": {
          "$.grossAnnual": 35000,
          "$.pensionPct": 0
        },
        "expect": {
          "$.personalAllowance": 12570,
          "$.taxableIncome": 22430,
          "$.incomeTax": 4486,
          "$.ni": 1794.4,
          "$.netAnnual": 28719.6,
          "$.netMonthly": 2393.3
        }
      },
      {
        "description": "S3 130,000 GBP — personal allowance fully tapered",
        "given": {
          "$.grossAnnual": 130000,
          "$.pensionPct": 0
        },
        "expect": {
          "$.personalAllowance": 0,
          "$.taxableIncome": 130000
        }
      }
    ]
  }
}