{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://askcalculators.com/calculator/permutation-and-combination-calculator/schema.json",
  "title": "Permutation and Combination Calculator inputs",
  "description": "Calculate exact permutations and combinations with or without replacement.",
  "type": "object",
  "properties": {
    "totalItems": {
      "title": "Total amount in the set (n)",
      "type": "number",
      "default": 6,
      "minimum": 0,
      "maximum": 500,
      "x-step": 1,
      "multipleOf": 1
    },
    "selectedItems": {
      "title": "Amount in each subset (r)",
      "type": "number",
      "default": 2,
      "minimum": 0,
      "maximum": 500,
      "x-step": 1,
      "multipleOf": 1
    },
    "replacement": {
      "title": "Selection rule",
      "type": "string",
      "default": "without",
      "enum": [
        "without",
        "with"
      ],
      "x-optionLabels": {
        "without": "Without replacement",
        "with": "With replacement"
      }
    }
  },
  "required": [
    "totalItems",
    "selectedItems",
    "replacement"
  ],
  "additionalProperties": false,
  "x-askcalculators": {
    "version": "1.0.0",
    "calculatorUrl": "https://askcalculators.com/calculator/permutation-and-combination-calculator/",
    "queryExample": "https://askcalculators.com/calculator/permutation-and-combination-calculator/?totalItems=6&selectedItems=2&replacement=without",
    "migrationStatus": "new",
    "reviewStatus": "pending",
    "pageStatus": "live",
    "workStatus": "pending",
    "formula": {
      "expression": "Without replacement: nPᵣ=n!/(n−r)! and nCᵣ=n!/[r!(n−r)!]; with replacement: nʳ and C(n+r−1,r)."
    },
    "quality": {
      "availability": "live",
      "technicalReviewRecord": "/reviews/permutation-and-combination-calculator.json",
      "qualifiedReview": "pending",
      "qualifiedReviewer": null,
      "qualifiedReviewDate": null,
      "formulaVersion": "1.0.0",
      "referenceCoverage": "references-listed",
      "releaseTestScope": "Catalog and regression checks are not a professional formula audit; consult release evidence.",
      "historicalMetadataDate": "2026-08-25",
      "historicalMetadataNotice": "The imported date is not evidence of a completed human review."
    },
    "outputs": {
      "permutations": {
        "title": "Permutations",
        "type": "string",
        "x-format": "text",
        "x-primary": true
      },
      "combinations": {
        "title": "Combinations",
        "type": "string",
        "x-format": "text"
      },
      "permutationFormula": {
        "title": "Permutation formula",
        "type": "string",
        "x-format": "text"
      },
      "combinationFormula": {
        "title": "Combination formula",
        "type": "string",
        "x-format": "text"
      }
    }
  }
}