{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://askcalculators.com/us/stair/schema.json",
  "title": "Stair Calculator inputs",
  "description": "Determine the riser height, number of steps, and total run for a stair stringer. Add editable USD material and labor prices and compare low, middle and high budget scenarios.",
  "type": "object",
  "properties": {
    "unitSystem": {
      "title": "Dimension units",
      "type": "string",
      "description": "Changing this selector converts dimensions already entered. Prices keep the purchasing unit printed beside each price.",
      "default": "imperial",
      "enum": [
        "imperial",
        "metric"
      ],
      "x-optionLabels": {
        "imperial": "US customary (ft, in)",
        "metric": "Metric (m, cm)"
      }
    },
    "totalRise": {
      "title": "Total rise (in / cm)",
      "type": "number",
      "default": 108
    },
    "targetRise": {
      "title": "Target rise (in / cm)",
      "type": "number",
      "default": 7
    },
    "treadDepth": {
      "title": "Tread going (in / cm)",
      "type": "number",
      "description": "Entered geometry, not a verified minimum under your building code.",
      "default": 10,
      "minimum": 0,
      "x-step": 0.01
    },
    "unitCost": {
      "title": "Material price (USD / tread)",
      "type": "number",
      "description": "Zero means unpriced. Use a current supplier quote; do not treat zero as free.",
      "default": 0,
      "minimum": 0,
      "x-step": 0.01,
      "x-unit": "currency"
    },
    "laborCost": {
      "title": "Total labor allowance (USD)",
      "type": "number",
      "default": 0,
      "minimum": 0,
      "x-step": 0.01,
      "x-unit": "currency"
    },
    "deliveryCost": {
      "title": "Delivery allowance (USD)",
      "type": "number",
      "default": 0,
      "minimum": 0,
      "x-step": 0.01,
      "x-unit": "currency"
    },
    "costSpreadPercent": {
      "title": "Low/high variation around entered subtotal (%)",
      "type": "number",
      "description": "A user-adjustable planning scenario, not a researched local price range.",
      "default": 15,
      "minimum": 0,
      "maximum": 100,
      "x-step": 1,
      "multipleOf": 1,
      "x-unit": "percent"
    }
  },
  "required": [],
  "additionalProperties": false,
  "x-askcalculators": {
    "version": "20.13.0",
    "calculatorUrl": "https://askcalculators.com/us/stair/",
    "queryExample": "https://askcalculators.com/us/stair/?totalRise=108&targetRise=7&treadDepth=10&unitCost=30&laborCost=500&deliveryCost=30&costSpreadPercent=15",
    "migrationStatus": "migrated",
    "reviewStatus": "pending",
    "pageStatus": "live",
    "workStatus": "pending",
    "migratedDate": "2026-09-10",
    "formula": {
      "expression": "Riser count = rounded total rise ÷ target riser height; actual riser = total rise ÷ riser count; tread/run values follow the selected stair geometry.; material = unrounded purchase quantity × entered unit price; middle = material + labor + delivery; low/high = middle × (1 ∓ variation/100)"
    },
    "quality": {
      "availability": "live",
      "technicalReviewRecord": "/reviews/stair-calculator.json",
      "qualifiedReview": "pending",
      "qualifiedReviewer": null,
      "qualifiedReviewDate": null,
      "formulaVersion": "20.13.0",
      "referenceCoverage": "references-listed",
      "releaseTestScope": "Catalog and regression checks are not a professional formula audit; consult release evidence.",
      "historicalMetadataDate": "2026-08-18",
      "historicalMetadataNotice": "The imported date is not evidence of a completed human review."
    },
    "outputs": {
      "numRisers": {
        "title": "Risers",
        "type": "number",
        "x-format": "number",
        "x-primary": true
      },
      "actualRise": {
        "title": "Actual rise (in)",
        "type": "number",
        "x-format": "number",
        "x-digits": 3
      },
      "riseCentimetres": {
        "title": "Actual rise (cm)",
        "type": "number",
        "x-format": "number",
        "x-digits": 3
      },
      "numTreads": {
        "title": "Treads",
        "type": "number",
        "x-format": "number"
      },
      "totalRun": {
        "title": "Total run (in)",
        "type": "number",
        "x-format": "number"
      },
      "runMetres": {
        "title": "Total run (m)",
        "type": "number",
        "x-format": "number",
        "x-digits": 3
      },
      "materialCost": {
        "title": "Material cost",
        "type": "number",
        "x-format": "currency",
        "x-currency": "USD"
      },
      "laborCost": {
        "title": "Labor allowance",
        "type": "number",
        "x-format": "currency",
        "x-currency": "USD"
      },
      "deliveryCost": {
        "title": "Delivery allowance",
        "type": "number",
        "x-format": "currency",
        "x-currency": "USD"
      },
      "unitRate": {
        "title": "Entered USD rate / tread",
        "type": "number",
        "x-format": "currency",
        "x-currency": "USD"
      },
      "estimatedTotal": {
        "title": "Entered subtotal",
        "type": "number",
        "x-format": "currency",
        "x-currency": "USD"
      },
      "costLow": {
        "title": "Low budget scenario",
        "type": "number",
        "x-format": "currency",
        "x-currency": "USD"
      },
      "costMid": {
        "title": "Middle budget scenario",
        "type": "number",
        "x-format": "currency",
        "x-currency": "USD"
      },
      "costHigh": {
        "title": "High budget scenario",
        "type": "number",
        "x-format": "currency",
        "x-currency": "USD"
      },
      "pricingStatus": {
        "title": "Pricing status",
        "type": "string",
        "x-format": "text"
      }
    }
  }
}