{
  "id": "lot-size",
  "version": "ffe678c8a98c",
  "status": "published",
  "name": "Lot Size Calculator",
  "question": "What lot size should I trade?",
  "summary": "Works out the forex lot size (position size) that risks a chosen percent of your account if the stop loss is hit, in standard, mini and micro lots and units, from rates you type.",
  "category": "finance",
  "subcategory": "investing",
  "url": "https://www.acalculator.org/finance/lot-size-calculator",
  "markdown": "https://www.acalculator.org/finance/lot-size-calculator.md",
  "kind": "function",
  "method": "risk = balance × risk %; pip value per lot = 100,000 × pip size × (1, 1 ÷ price, or the quote-currency rate); lots = risk ÷ (stop pips × pip value per lot).",
  "assumptions": [
    "A standard lot is 100,000 units of the base currency; a mini lot 10,000; a micro lot 1,000.",
    "The pair price and the conversion rate are typed by you; the page fetches no quotes.",
    "Spread, commission, swap and slippage are not counted; a gap past the stop loses more.",
    "Arithmetic is exact on the typed decimals; the rounded size is cut down, never up, to 0.01 lot."
  ],
  "inputs": {
    "$schema": "https://json-schema.org/draft/2020-12/schema",
    "type": "object",
    "properties": {
      "balance": {
        "title": "Account balance",
        "description": "The money in your trading account, in its own currency.",
        "type": "number",
        "minimum": 1,
        "maximum": 1000000000000
      },
      "risk": {
        "title": "Risk per trade",
        "description": "The share of the balance you accept to lose if the stop loss is hit.",
        "type": "number",
        "x-unit": "percent",
        "exclusiveMinimum": 0,
        "maximum": 100
      },
      "stop": {
        "title": "Stop loss (pips)",
        "description": "How far the stop loss is from the entry price, in pips.",
        "type": "number",
        "minimum": 0.1,
        "maximum": 100000
      },
      "pip": {
        "title": "Pip size",
        "description": "One pip in the pair’s price: 0.0001 for most pairs, 0.01 for pairs quoted in Japanese yen.",
        "type": "string",
        "enum": [
          "0.0001",
          "0.01"
        ]
      },
      "acct": {
        "title": "Your account currency is",
        "description": "The pair’s quote (second) currency, its base (first) currency, or neither; it sets how a pip converts to your money.",
        "type": "string",
        "enum": [
          "quote",
          "base",
          "other"
        ]
      },
      "price": {
        "title": "Pair price",
        "description": "The pair’s price: how much quote currency one unit of the base currency buys, such as 150 for USD/JPY.",
        "type": "number",
        "minimum": 0.000001,
        "maximum": 1000000
      },
      "conv": {
        "title": "Quote currency in account currency",
        "description": "What one unit of the quote currency is worth in your account currency, such as 1.25 USD per GBP.",
        "type": "number",
        "minimum": 0.000001,
        "maximum": 1000000
      }
    }
  },
  "outputs": {
    "lots": {
      "label": "Standard lots",
      "description": "The position size in standard lots of 100,000 units of the base currency.",
      "format": "number"
    },
    "units": {
      "label": "Units",
      "description": "The position size in units of the base currency.",
      "format": "number"
    },
    "mini": {
      "label": "Mini lots",
      "description": "The size in mini lots of 10,000 units.",
      "format": "number"
    },
    "micro": {
      "label": "Micro lots",
      "description": "The size in micro lots of 1,000 units.",
      "format": "number"
    },
    "riskAmount": {
      "label": "Money at risk",
      "description": "Balance × risk per trade: what you lose if the stop loss is hit.",
      "format": "number"
    },
    "pipValue": {
      "label": "Pip value per standard lot",
      "description": "What one pip is worth in your account currency for one standard lot.",
      "format": "number"
    },
    "roundedLots": {
      "label": "Lots rounded down to 0.01",
      "description": "The size most platforms accept: the standard lots rounded down to the nearest 0.01.",
      "format": "number"
    },
    "roundedRisk": {
      "label": "Money at risk at the rounded size",
      "description": "Rounded lots × stop loss × pip value per lot.",
      "format": "number"
    }
  },
  "defaultAnswer": {
    "inputs": {
      "balance": 10000,
      "risk": 1,
      "stop": 50,
      "pip": "0.0001",
      "acct": "quote",
      "price": 150,
      "conv": 1.25
    },
    "outputs": {
      "lots": 0.2,
      "units": 20000,
      "mini": 2,
      "micro": 20,
      "riskAmount": 100,
      "pipValue": 10,
      "roundedLots": 0.2,
      "roundedRisk": 100
    },
    "text": "Risking 100 with a 50-pip stop, trade 0.2 standard lots (20,000 units)."
  },
  "examples": [
    {
      "given": {
        "balance": 10000,
        "risk": 1,
        "stop": 50,
        "pip": "0.0001",
        "acct": "quote"
      },
      "expect": {
        "riskAmount": 100,
        "pipValue": 10,
        "lots": 0.2,
        "units": 20000,
        "mini": 2,
        "micro": 20,
        "roundedLots": 0.2
      },
      "source": "hand calculation in content.mdx: 10,000 × 1% = 100; 100,000 × 0.0001 = 10 per pip; 100 ÷ (50 × 10) = 0.2 lots; Commodity Futures Trading Commission, CFTC Glossary (\"Pip\": the smallest price unit of a commodity or currency). https://www.cftc.gov/LearnandProtect/AdvisoriesAndArticles/CFTCGlossary/index.htm"
    },
    {
      "given": {
        "balance": 5000,
        "risk": 2,
        "stop": 30,
        "pip": "0.01",
        "acct": "base",
        "price": 150
      },
      "expect": {
        "riskAmount": 100,
        "pipValue": 6.666666666666667,
        "lots": 0.5,
        "units": 50000
      },
      "source": "hand calculation in content.mdx: 100,000 × 0.01 ÷ 150 = 6.6667 per pip; 100 ÷ (30 × 6.6667) = 0.5 lots; Commodity Futures Trading Commission, CFTC Glossary (\"Pip\": the smallest price unit of a commodity or currency). https://www.cftc.gov/LearnandProtect/AdvisoriesAndArticles/CFTCGlossary/index.htm"
    },
    {
      "given": {
        "balance": 20000,
        "risk": 1.5,
        "stop": 40,
        "pip": "0.0001",
        "acct": "other",
        "conv": 1.25
      },
      "expect": {
        "riskAmount": 300,
        "pipValue": 12.5,
        "lots": 0.6
      },
      "source": "hand calculation in content.mdx: 100,000 × 0.0001 × 1.25 = 12.5 per pip; 300 ÷ (40 × 12.5) = 0.6 lots; Commodity Futures Trading Commission, CFTC Glossary (\"Pip\": the smallest price unit of a commodity or currency). https://www.cftc.gov/LearnandProtect/AdvisoriesAndArticles/CFTCGlossary/index.htm"
    },
    {
      "given": {
        "balance": 2500,
        "risk": 1,
        "stop": 35,
        "pip": "0.0001",
        "acct": "quote"
      },
      "expect": {
        "lots": 0.07142857142857142,
        "roundedLots": 0.07,
        "roundedRisk": 24.5
      },
      "source": "hand calculation in content.mdx: 25 ÷ (35 × 10) = 0.0714 lots, rounded down to 0.07; 0.07 × 35 × 10 = 24.50; Commodity Futures Trading Commission, CFTC Glossary (\"Pip\": the smallest price unit of a commodity or currency). https://www.cftc.gov/LearnandProtect/AdvisoriesAndArticles/CFTCGlossary/index.htm"
    }
  ],
  "sources": [
    "Commodity Futures Trading Commission, CFTC Glossary (\"Pip\": the smallest price unit of a commodity or currency). https://www.cftc.gov/LearnandProtect/AdvisoriesAndArticles/CFTCGlossary/index.htm (retrieved 2026-10-02)"
  ],
  "related": [
    "options-profit",
    "stock-profit",
    "roi"
  ],
  "changelog": []
}