cz.freelax/tax-engine

{
  "type": "object",
  "properties": {
    "taxYear": {
      "default": 2026,
      "description": "Only 2026 is supported because the engine currently has a 2026 ruleset",
      "type": "number",
      "const": 2026
    },
    "monthlyBusinessIncome": {
      "description": "Gross monthly business income in CZK (§ 7 ZDP)",
      "type": "number",
      "minimum": 0,
      "maximum": 100000000
    },
    "annualBusinessIncome": {
      "description": "Exact annual business income in CZK; takes precedence over the monthly figure",
      "type": "number",
      "minimum": 0,
      "maximum": 100000000
    },
    "rentalMonthlyIncome": {
      "default": 0,
      "type": "number",
      "minimum": 0,
      "maximum": 100000000
    },
    "taxRegime": {
      "default": "standard",
      "type": "string",
      "enum": [
        "standard",
        "pausal_band_1",
        "pausal_band_2",
        "pausal_band_3"
      ]
    },
    "targetRegime": {
      "description": "Simulate a different regime without changing the stored facts",
      "type": "string",
      "enum": [
        "standard",
        "pausal_band_1",
        "pausal_band_2",
        "pausal_band_3"
      ]
    },
    "activityType": {
      "default": "main",
      "type": "string",
      "enum": [
        "main",
        "secondary"
      ]
    },
    "flatRatePercent": {
      "default": 0.6,
      "description": "Flat-rate expense percentage as a decimal (0.4 / 0.6 / 0.8)",
      "anyOf": [
        {
          "type": "number",
          "const": 0.4
        },
        {
          "type": "number",
          "const": 0.6
        },
        {
          "type": "number",
          "const": 0.8
        }
      ]
    },
    "citizenshipType": {
      "default": "eu",
      "type": "string",
      "enum": [
        "eu",
        "non_eu_public",
        "non_eu_private"
      ]
    },
    "publicHealthStatus": {
      "type": "string",
      "enum": [
        "public",
        "outside",
        "unknown"
      ]
    },
    "isCzechTaxResident": {
      "default": true,
      "type": "boolean"
    },
    "isVATRegistered": {
      "default": false,
      "type": "boolean"
    },
    "employerCoversHealth": {
      "default": false,
      "type": "boolean"
    },
    "isNewOsvc": {
      "default": false,
      "type": "boolean"
    },
    "hasReducedSocialMinimum": {
      "default": false,
      "type": "boolean"
    },
    "isExemptFromMonthlyZalohy": {
      "default": false,
      "type": "boolean"
    },
    "isMarried": {
      "default": false,
      "type": "boolean"
    },
    "spouseIncomeUnderLimit": {
      "description": "Spouse annual income under the sleva na manžela limit",
      "type": "boolean"
    },
    "hasChildUnder3": {
      "type": "boolean"
    },
    "children": {
      "default": [],
      "maxItems": 10,
      "type": "array",
      "items": {
        "type": "object",
        "properties": {
          "birthYear": {
            "type": "integer",
            "minimum": 1950,
            "maximum": 2030
          },
          "hasZTP": {
            "default": false,
            "type": "boolean"
          },
          "isStudying": {
            "default": false,
            "type": "boolean"
          }
        },
        "required": [
          "birthYear"
        ],
        "additionalProperties": false
      }
    },
    "disabilityGrade": {
      "default": "none",
      "type": "string",
      "enum": [
        "none",
        "grade_1_2",
        "grade_3"
      ]
    },
    "hasZTP": {
      "default": false,
      "type": "boolean"
    },
    "deductions": {
      "type": "object",
      "properties": {
        "pensionContributions": {
          "type": "number",
          "minimum": 0
        },
        "lifeInsuranceContributions": {
          "type": "number",
          "minimum": 0
        },
        "dipContributions": {
          "type": "number",
          "minimum": 0
        },
        "mortgageInterestPaid": {
          "type": "number",
          "minimum": 0
        },
        "mortgageLoanYear": {
          "type": "integer",
          "minimum": 1990,
          "maximum": 2030
        },
        "mortgageIsOwnHousing": {
          "type": "boolean"
        }
      },
      "additionalProperties": false
    }
  },
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "additionalProperties": false
}

{
  "type": "object",
  "properties": {
    "monthlyIncome": {
      "type": "number",
      "minimum": 0,
      "maximum": 100000000,
      "description": "Gross monthly business income in CZK (§ 7 ZDP)"
    },
    "rentalMonthlyIncome": {
      "description": "Monthly rental income in CZK (§ 9 ZDP); triggers the mixed-income calculation",
      "type": "number",
      "minimum": 0,
      "maximum": 100000000
    },
    "taxRegime": {
      "default": "standard",
      "type": "string",
      "enum": [
        "standard",
        "pausal_band_1",
        "pausal_band_2",
        "pausal_band_3"
      ]
    },
    "activityType": {
      "default": "main",
      "type": "string",
      "enum": [
        "main",
        "secondary"
      ]
    },
    "flatRatePercent": {
      "default": 0.6,
      "anyOf": [
        {
          "type": "number",
          "const": 0.4
        },
        {
          "type": "number",
          "const": 0.6
        },
        {
          "type": "number",
          "const": 0.8
        }
      ],
      "description": "Flat-rate expense percentage as a decimal: 0.4 (other business), 0.6 (most freelancers / živnost volná), 0.8 (craft trades)"
    },
    "advanceExempt": {
      "default": false,
      "type": "boolean"
    },
    "reducedMinimumBase": {
      "default": false,
      "description": "New OSVČ in the first 2 years (lower social minimum)",
      "type": "boolean"
    },
    "employerCoversHealth": {
      "default": false,
      "type": "boolean"
    },
    "secondaryThresholdExceeded": {
      "default": false,
      "type": "boolean"
    }
  },
  "required": [
    "monthlyIncome"
  ],
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "additionalProperties": false
}

{
  "type": "object",
  "properties": {
    "annualIncome": {
      "type": "number",
      "minimum": 0,
      "maximum": 100000000,
      "description": "Gross annual business income in CZK"
    },
    "flatRatePercent": {
      "default": 0.6,
      "anyOf": [
        {
          "type": "number",
          "const": 0.4
        },
        {
          "type": "number",
          "const": 0.6
        },
        {
          "type": "number",
          "const": 0.8
        }
      ],
      "description": "Flat-rate expense percentage as a decimal: 0.4 (other business), 0.6 (most freelancers / živnost volná), 0.8 (craft trades)"
    },
    "isMarried": {
      "type": "boolean"
    },
    "numberOfChildren": {
      "type": "integer",
      "minimum": 0,
      "maximum": 10
    },
    "spouseIncomeUnderLimit": {
      "description": "Spouse annual income under the credit limit (sleva na manžela/manželku)",
      "type": "boolean"
    },
    "hasChildUnder3": {
      "type": "boolean"
    },
    "rentalAnnualIncome": {
      "type": "number",
      "minimum": 0,
      "maximum": 100000000
    },
    "deductions": {
      "type": "object",
      "properties": {
        "pensionContributions": {
          "type": "number",
          "minimum": 0
        },
        "lifeInsuranceContributions": {
          "type": "number",
          "minimum": 0
        },
        "dipContributions": {
          "type": "number",
          "minimum": 0
        },
        "mortgageInterestPaid": {
          "type": "number",
          "minimum": 0
        },
        "mortgageLoanYear": {
          "type": "integer",
          "minimum": 1990,
          "maximum": 2030
        },
        "mortgageIsOwnHousing": {
          "type": "boolean"
        }
      },
      "additionalProperties": false
    }
  },
  "required": [
    "annualIncome"
  ],
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "additionalProperties": false
}

{
  "type": "object",
  "properties": {
    "currentBand": {
      "type": "string",
      "enum": [
        "band1",
        "band2",
        "band3"
      ],
      "description": "Band actually paid during the year"
    },
    "actualAnnualIncome": {
      "type": "number",
      "minimum": 0,
      "maximum": 100000000
    },
    "monthsInRegime": {
      "default": 12,
      "type": "integer",
      "minimum": 1,
      "maximum": 12
    },
    "isProjection": {
      "default": false,
      "description": "True for a mid-year projection instead of a final settlement",
      "type": "boolean"
    },
    "flatRatePercent": {
      "anyOf": [
        {
          "type": "number",
          "const": 0.4
        },
        {
          "type": "number",
          "const": 0.6
        },
        {
          "type": "number",
          "const": 0.8
        }
      ],
      "description": "Flat-rate expense percentage as a decimal: 0.4 (other business), 0.6 (most freelancers / živnost volná), 0.8 (craft trades)"
    }
  },
  "required": [
    "currentBand",
    "actualAnnualIncome"
  ],
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "additionalProperties": false
}

{
  "type": "object",
  "properties": {
    "obligationType": {
      "type": "string",
      "enum": [
        "health",
        "social",
        "tax_advance",
        "pausal",
        "pausal_oznameni",
        "pausal_doplatek",
        "tax_return",
        "prehled_social",
        "prehled_health",
        "annual_social"
      ],
      "description": "Obligation family: health/social insurance debt, tax_advance (záloha na daň), pausal (paušální daň payment), tax_return (late filing), prehled_* (late Přehled), annual_social (doplatek)"
    },
    "owedAmount": {
      "type": "number",
      "minimum": 0,
      "maximum": 100000000,
      "description": "Outstanding amount in CZK"
    },
    "daysOverdue": {
      "type": "integer",
      "minimum": 0,
      "maximum": 3650
    },
    "gracePeriodActive": {
      "default": false,
      "type": "boolean"
    },
    "dueDate": {
      "description": "Original due date (YYYY-MM-DD); anchors the correct half-year repo rate",
      "type": "string",
      "format": "date",
      "pattern": "^(?:(?:\\d\\d[2468][048]|\\d\\d[13579][26]|\\d\\d0[48]|[02468][048]00|[13579][26]00)-02-29|\\d{4}-(?:(?:0[13578]|1[02])-(?:0[1-9]|[12]\\d|3[01])|(?:0[469]|11)-(?:0[1-9]|[12]\\d|30)|(?:02)-(?:0[1-9]|1\\d|2[0-8])))$"
    }
  },
  "required": [
    "obligationType",
    "owedAmount",
    "daysOverdue"
  ],
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "additionalProperties": false
}

{
  "type": "object",
  "properties": {
    "amountEur": {
      "type": "number",
      "exclusiveMinimum": 0,
      "maximum": 1000000000,
      "description": "Amount in EUR"
    }
  },
  "required": [
    "amountEur"
  ],
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "additionalProperties": false
}

{
  "type": "object",
  "properties": {
    "taxYear": {
      "type": "integer",
      "minimum": 2020,
      "maximum": 2030,
      "description": "The tax year the return is FOR (e.g. 2025 return is filed in 2026)"
    },
    "route": {
      "type": "string",
      "enum": [
        "standard_deadline",
        "self_electronic_extension",
        "advisor_extension"
      ],
      "description": "Filing route: standard_deadline = paper/no extension (1 April), self_electronic_extension = filed electronically after 1 April (+1 month), advisor_extension = filed by a tax advisor (1 July)"
    }
  },
  "required": [
    "taxYear"
  ],
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "additionalProperties": false
}

{
  "type": "object",
  "properties": {
    "taxYear": {
      "type": "integer",
      "minimum": 2020,
      "maximum": 2030
    },
    "route": {
      "type": "string",
      "enum": [
        "standard_deadline",
        "self_electronic_extension",
        "advisor_extension"
      ],
      "description": "Filing route: standard_deadline = paper/no extension (1 April), self_electronic_extension = filed electronically after 1 April (+1 month), advisor_extension = filed by a tax advisor (1 July)"
    }
  },
  "required": [
    "taxYear"
  ],
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "additionalProperties": false
}

{
  "type": "object",
  "properties": {
    "year": {
      "type": "integer",
      "minimum": 2020,
      "maximum": 2030
    },
    "date": {
      "description": "Optional date (YYYY-MM-DD) to test for working-day status",
      "type": "string",
      "format": "date",
      "pattern": "^(?:(?:\\d\\d[2468][048]|\\d\\d[13579][26]|\\d\\d0[48]|[02468][048]00|[13579][26]00)-02-29|\\d{4}-(?:(?:0[13578]|1[02])-(?:0[1-9]|[12]\\d|3[01])|(?:0[469]|11)-(?:0[1-9]|[12]\\d|30)|(?:02)-(?:0[1-9]|1\\d|2[0-8])))$"
    }
  },
  "required": [
    "year"
  ],
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "additionalProperties": false
}

{
  "type": "object",
  "properties": {
    "annualIncome": {
      "type": "number",
      "minimum": 0,
      "maximum": 100000000,
      "description": "Expected annual business income in CZK"
    },
    "citizenshipType": {
      "description": "eu = EU/EEA citizen; non_eu_public = non-EU participating in Czech public health insurance (e.g. dočasná ochrana, employment); non_eu_private = non-EU with private/commercial insurance only",
      "type": "string",
      "enum": [
        "eu",
        "non_eu_public",
        "non_eu_private"
      ]
    },
    "publicHealthStatus": {
      "type": "string",
      "enum": [
        "public",
        "outside",
        "unknown"
      ]
    },
    "isVATRegistered": {
      "description": "Full VAT payer (plátce DPH). Identifikovaná osoba is NOT blocking.",
      "type": "boolean"
    },
    "activityType": {
      "type": "string",
      "enum": [
        "main",
        "secondary"
      ]
    },
    "rentalAnnualIncome": {
      "type": "number",
      "minimum": 0,
      "maximum": 100000000
    }
  },
  "required": [
    "annualIncome"
  ],
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "additionalProperties": false
}

{
  "type": "object",
  "properties": {
    "annualIncome": {
      "type": "number",
      "minimum": 0,
      "maximum": 100000000
    },
    "flatRatePercent": {
      "default": 0.6,
      "anyOf": [
        {
          "type": "number",
          "const": 0.4
        },
        {
          "type": "number",
          "const": 0.6
        },
        {
          "type": "number",
          "const": 0.8
        }
      ],
      "description": "Flat-rate expense percentage as a decimal: 0.4 (other business), 0.6 (most freelancers / živnost volná), 0.8 (craft trades)"
    }
  },
  "required": [
    "annualIncome"
  ],
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "additionalProperties": false
}

{
  "type": "object",
  "properties": {
    "annualIncome": {
      "type": "number",
      "minimum": 0,
      "maximum": 100000000
    }
  },
  "required": [
    "annualIncome"
  ],
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "additionalProperties": false
}

{
  "type": "object",
  "properties": {
    "vatStatus": {
      "type": "string",
      "enum": [
        "unknown",
        "not_registered",
        "identified_person",
        "vat_payer"
      ],
      "description": "Current VAT status of the OSVČ"
    },
    "vatStatusConfirmedAt": {
      "description": "When the VAT status was last confirmed (freshness window 180 days)",
      "type": "string",
      "format": "date",
      "pattern": "^(?:(?:\\d\\d[2468][048]|\\d\\d[13579][26]|\\d\\d0[48]|[02468][048]00|[13579][26]00)-02-29|\\d{4}-(?:(?:0[13578]|1[02])-(?:0[1-9]|[12]\\d|3[01])|(?:0[469]|11)-(?:0[1-9]|[12]\\d|30)|(?:02)-(?:0[1-9]|1\\d|2[0-8])))$"
    },
    "foreignServicePurchase": {
      "type": "string",
      "enum": [
        "unknown",
        "none_confirmed",
        "possible",
        "qualifying_confirmed"
      ],
      "description": "Foreign service purchases: none_confirmed = verified none, possible = maybe (e.g. runs online ads), qualifying_confirmed = a qualifying purchase from a non-CZ supplier is confirmed"
    },
    "foreignServicePurchaseConfirmedAt": {
      "type": "string",
      "format": "date",
      "pattern": "^(?:(?:\\d\\d[2468][048]|\\d\\d[13579][26]|\\d\\d0[48]|[02468][048]00|[13579][26]00)-02-29|\\d{4}-(?:(?:0[13578]|1[02])-(?:0[1-9]|[12]\\d|3[01])|(?:0[469]|11)-(?:0[1-9]|[12]\\d|30)|(?:02)-(?:0[1-9]|1\\d|2[0-8])))$"
    },
    "purchaseDate": {
      "description": "Date of the qualifying purchase; drives the 15-day § 97 registration deadline",
      "type": "string",
      "format": "date",
      "pattern": "^(?:(?:\\d\\d[2468][048]|\\d\\d[13579][26]|\\d\\d0[48]|[02468][048]00|[13579][26]00)-02-29|\\d{4}-(?:(?:0[13578]|1[02])-(?:0[1-9]|[12]\\d|3[01])|(?:0[469]|11)-(?:0[1-9]|[12]\\d|30)|(?:02)-(?:0[1-9]|1\\d|2[0-8])))$"
    },
    "foreignSales": {
      "description": "Year-to-date foreign client income for the sales-side (§ 6i) check",
      "maxItems": 100,
      "type": "array",
      "items": {
        "type": "object",
        "properties": {
          "amount": {
            "type": "number",
            "minimum": 0,
            "maximum": 100000000
          },
          "clientLocation": {
            "type": "string",
            "enum": [
              "cz",
              "eu",
              "non_eu",
              "unknown"
            ]
          },
          "clientVatStatus": {
            "type": "string",
            "enum": [
              "business_vat_id",
              "business_no_vat_id",
              "consumer",
              "unknown"
            ]
          }
        },
        "required": [
          "amount"
        ],
        "additionalProperties": false
      }
    },
    "today": {
      "description": "Evaluation date; defaults to today",
      "type": "string",
      "format": "date",
      "pattern": "^(?:(?:\\d\\d[2468][048]|\\d\\d[13579][26]|\\d\\d0[48]|[02468][048]00|[13579][26]00)-02-29|\\d{4}-(?:(?:0[13578]|1[02])-(?:0[1-9]|[12]\\d|3[01])|(?:0[469]|11)-(?:0[1-9]|[12]\\d|30)|(?:02)-(?:0[1-9]|1\\d|2[0-8])))$"
    }
  },
  "required": [
    "vatStatus",
    "foreignServicePurchase"
  ],
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "additionalProperties": false
}

{
  "type": "object",
  "properties": {
    "topic": {
      "type": "string",
      "enum": [
        "pausalni_dan",
        "identifikovana_osoba",
        "dph_registrace",
        "zalohy",
        "prehledy",
        "penale",
        "danove_pasmo_23",
        "vedlejsi_cinnost"
      ]
    },
    "locale": {
      "default": "en",
      "type": "string",
      "enum": [
        "en",
        "cs"
      ]
    }
  },
  "required": [
    "topic"
  ],
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "additionalProperties": false
}