{
  "id": "percent-yield",
  "version": "b7fa85027d03",
  "status": "published",
  "name": "Percent Yield Calculator",
  "question": "What is my percent yield?",
  "summary": "Finds the percent yield of a reaction from the actual and theoretical yield, or works out the theoretical yield from the limiting reactant first.",
  "category": "chemistry",
  "subcategory": "stoichiometry",
  "url": "https://www.acalculator.org/chemistry/percent-yield-calculator",
  "markdown": "https://www.acalculator.org/chemistry/percent-yield-calculator.md",
  "kind": "function",
  "method": "Percent yield = actual yield ÷ theoretical yield × 100. From the limiting reactant: theoretical yield = reactant mass ÷ reactant molar mass × (product coefficient ÷ reactant coefficient) × product molar mass.",
  "assumptions": [
    "The reactant you type is the limiting reactant: the one that runs out first. Check it with the mole ratios before you use this mode.",
    "Molar masses are typed in g/mol; masses can be typed in g, mg, kg, oz or lb and are worked in grams.",
    "Each typed mass and molar mass is used as the exact decimal you typed; the result is rounded once."
  ],
  "inputs": {
    "$schema": "https://json-schema.org/draft/2020-12/schema",
    "type": "object",
    "properties": {
      "mode": {
        "title": "Theoretical yield",
        "description": "Type the theoretical yield, or let the page find it from the limiting reactant.",
        "type": "string",
        "enum": [
          "yields",
          "reactant"
        ]
      },
      "a": {
        "title": "Actual yield",
        "description": "The mass of product you obtained.",
        "type": [
          "number",
          "string"
        ],
        "x-quantity": "mass",
        "minimum": 0,
        "maximum": 1000
      },
      "t": {
        "title": "Theoretical yield",
        "description": "The mass of product the balanced equation predicts.",
        "type": [
          "number",
          "string"
        ],
        "x-quantity": "mass",
        "exclusiveMinimum": 0,
        "maximum": 1000
      },
      "r": {
        "title": "Mass of limiting reactant",
        "description": "The mass of the reactant that runs out first.",
        "type": [
          "number",
          "string"
        ],
        "x-quantity": "mass",
        "exclusiveMinimum": 0,
        "maximum": 1000
      },
      "mr": {
        "title": "Reactant molar mass",
        "description": "The molar mass of the limiting reactant, in g/mol.",
        "type": "number",
        "minimum": 0.1,
        "maximum": 100000
      },
      "cr": {
        "title": "Reactant coefficient",
        "description": "The limiting reactant’s coefficient in the balanced equation.",
        "type": "integer",
        "minimum": 1,
        "maximum": 1000
      },
      "cp": {
        "title": "Product coefficient",
        "description": "The product’s coefficient in the balanced equation.",
        "type": "integer",
        "minimum": 1,
        "maximum": 1000
      },
      "mp": {
        "title": "Product molar mass",
        "description": "The molar mass of the product, in g/mol.",
        "type": "number",
        "minimum": 0.1,
        "maximum": 100000
      }
    }
  },
  "outputs": {
    "percent": {
      "label": "Percent yield",
      "description": "Actual yield ÷ theoretical yield × 100.",
      "format": "percent"
    },
    "theoreticalGrams": {
      "label": "Theoretical yield (g)",
      "description": "The theoretical yield in grams.",
      "format": "number"
    },
    "actualGrams": {
      "label": "Actual yield (g)",
      "description": "The actual yield in grams.",
      "format": "number"
    },
    "productMoles": {
      "label": "Theoretical product (mol)",
      "description": "Moles of limiting reactant × product coefficient ÷ reactant coefficient.",
      "format": "number"
    },
    "note": {
      "label": "Note",
      "description": "Shown when the percent yield is over 100%.",
      "format": "text"
    }
  },
  "defaultAnswer": {
    "inputs": {
      "mode": "yields",
      "a": 0.00039200000000000004,
      "t": 0.0005072,
      "r": 0.001274,
      "mr": 159.62,
      "cr": 1,
      "cp": 1,
      "mp": 63.55
    },
    "outputs": {
      "percent": 77.28706624605678,
      "theoreticalGrams": 0.5072,
      "actualGrams": 0.392
    },
    "text": "Your percent yield is 77.29%: 0.392 g of 0.5072 g."
  },
  "examples": [
    {
      "given": {
        "mode": "yields",
        "a": 0.00039200000000000004,
        "t": 0.0005072
      },
      "expect": {
        "percent": 77.28706624605678,
        "theoreticalGrams": 0.5072,
        "actualGrams": 0.392
      },
      "source": "OpenStax, Chemistry 2e, §4.4 Reaction Yields, https://openstax.org/books/chemistry-2e/pages/4-4-reaction-yields (Example 4.13: 0.392 g ÷ 0.5072 g × 100% = 77.3%); Python 3: 0.392/0.5072*100"
    },
    {
      "given": {
        "mode": "reactant",
        "a": 0.00039200000000000004,
        "r": 0.001274,
        "mr": 159.62,
        "cr": 1,
        "cp": 1,
        "mp": 63.55
      },
      "expect": {
        "percent": 77.2837862373661,
        "theoreticalGrams": 0.5072215261245459,
        "productMoles": 0.007981455957900013
      },
      "source": "OpenStax, Chemistry 2e, §4.4 Reaction Yields, https://openstax.org/books/chemistry-2e/pages/4-4-reaction-yields (Example 4.13: 1.274 g CuSO₄ ÷ 159.62 g/mol × 63.55 g/mol = 0.5072 g Cu); Python 3 with fractions.Fraction"
    },
    {
      "given": {
        "mode": "reactant",
        "a": 0.0125,
        "r": 0.0329,
        "mr": 153.81,
        "cr": 1,
        "cp": 1,
        "mp": 120.91
      },
      "expect": {
        "percent": 48.332189105966684,
        "theoreticalGrams": 25.86268123008907
      },
      "source": "OpenStax, Chemistry 2e, §4.4 Reaction Yields, https://openstax.org/books/chemistry-2e/pages/4-4-reaction-yields (Check Your Learning after Example 4.13: 48.3%); Python 3 with fractions.Fraction"
    },
    {
      "given": {
        "mode": "reactant",
        "a": 0.01,
        "r": 0.004,
        "mr": 2,
        "cr": 2,
        "cp": 2,
        "mp": 18
      },
      "expect": {
        "percent": 27.77777777777778,
        "theoreticalGrams": 36,
        "productMoles": 2
      },
      "source": "hand calculation in content.mdx: 4 ÷ 2 = 2 mol H₂ × 2/2 = 2 mol H₂O × 18 = 36 g; 10 ÷ 36 = 27.78%; OpenStax, Chemistry 2e, §4.4 Reaction Yields, https://openstax.org/books/chemistry-2e/pages/4-4-reaction-yields"
    }
  ],
  "sources": [
    "OpenStax, Chemistry 2e, §4.4 Reaction Yields (percent yield = actual ÷ theoretical × 100%; Example 4.13 and its Check Your Learning). https://openstax.org/books/chemistry-2e/pages/4-4-reaction-yields (retrieved 2026-10-02)",
    "NIST Special Publication 811, Guide for the Use of the International System of Units, Appendix B (1 oz = 28.349523125 g, 1 lb = 453.59237 g). https://www.nist.gov/pml/special-publication-811 (retrieved 2026-10-02)"
  ],
  "related": [
    "mole",
    "molar-mass",
    "chemical-equation-balancer",
    "molarity"
  ],
  "changelog": []
}