{
  "id": "barbell-plate",
  "version": "095de420d940",
  "status": "published",
  "name": "Barbell Plate Calculator",
  "question": "What barbell plates do I load?",
  "summary": "Works out the plates to load on each side of a barbell for a target weight in pounds or kilograms, from the bar weight and the plate sizes you have, heaviest plates first.",
  "category": "sports",
  "subcategory": "lifting",
  "url": "https://www.acalculator.org/sports/barbell-plate-calculator",
  "markdown": "https://www.acalculator.org/sports/barbell-plate-calculator.md",
  "kind": "function",
  "method": "Per side = (target − bar) ÷ 2. Going from the heaviest plate size to the lightest, load as many of each as fit in what is left of the side.",
  "assumptions": [
    "Each plate size can be used as many times as needed, and both sides are loaded the same.",
    "Plates are chosen heaviest first, the way lifters load a bar; this is not always the fewest plates (60 lb per side is 45, 10, 5 rather than 35, 25).",
    "Collars are not counted; add their weight to the bar weight if you use them."
  ],
  "inputs": {
    "$schema": "https://json-schema.org/draft/2020-12/schema",
    "type": "object",
    "properties": {
      "unit": {
        "title": "Units",
        "description": "Pounds or kilograms, for the target, the bar and the plates.",
        "type": "string",
        "enum": [
          "lb",
          "kg"
        ]
      },
      "w": {
        "title": "Target weight (lb)",
        "description": "The total weight to lift: the bar plus every plate.",
        "type": "number",
        "minimum": 0,
        "maximum": 10000
      },
      "bar": {
        "title": "Bar weight (lb)",
        "description": "The weight of the empty bar (an Olympic bar is often 45 lb).",
        "type": "number",
        "minimum": 0,
        "maximum": 10000
      },
      "plb": {
        "title": "Plates you have (lb)",
        "description": "The plate sizes you can load, in lb, separated by spaces. Each size is used in pairs, as many as needed.",
        "type": "array",
        "items": {
          "type": "number"
        }
      },
      "wkg": {
        "title": "Target weight (kg)",
        "description": "The total weight to lift: the bar plus every plate.",
        "type": "number",
        "minimum": 0,
        "maximum": 10000
      },
      "barkg": {
        "title": "Bar weight (kg)",
        "description": "The weight of the empty bar (a men’s Olympic bar is 20 kg).",
        "type": "number",
        "minimum": 0,
        "maximum": 10000
      },
      "pkg": {
        "title": "Plates you have (kg)",
        "description": "The plate sizes you can load, in kg, separated by spaces. Each size is used in pairs, as many as needed.",
        "type": "array",
        "items": {
          "type": "number"
        }
      }
    }
  },
  "outputs": {
    "plates": {
      "label": "Plates on each side",
      "description": "The plates to load on each side, heaviest first; 2 × 45 means two 45s on each side.",
      "format": "text"
    },
    "perSide": {
      "label": "Weight per side",
      "description": "(target − bar) ÷ 2.",
      "format": "number"
    },
    "count": {
      "label": "Plates per side",
      "description": "How many plates go on each side.",
      "format": "integer"
    },
    "loaded": {
      "label": "Total loaded",
      "description": "The bar plus both sides as loaded: equal to the target unless the plates cannot make it exactly.",
      "format": "number"
    },
    "short": {
      "label": "Short of target",
      "description": "Target − total loaded: 0 when the plates make the target exactly.",
      "format": "number"
    }
  },
  "defaultAnswer": {
    "inputs": {
      "unit": "lb",
      "w": 225,
      "bar": 45,
      "plb": "45 35 25 10 5 2.5",
      "wkg": 100,
      "barkg": 20,
      "pkg": "25 20 15 10 5 2.5 1.25"
    },
    "outputs": {
      "plates": "2 × 45",
      "perSide": 90,
      "count": 2,
      "loaded": 225,
      "short": 0
    },
    "text": "Load 2 × 45 on each side, for 225 in total."
  },
  "examples": [
    {
      "given": {
        "unit": "lb",
        "w": 225,
        "bar": 45,
        "plb": [
          45,
          35,
          25,
          10,
          5,
          2.5
        ]
      },
      "expect": {
        "plates": "2 × 45",
        "perSide": 90,
        "count": 2,
        "loaded": 225,
        "short": 0
      },
      "source": "hand calculation in content.mdx: (225 − 45) ÷ 2 = 90 = 45 + 45; Wikipedia, Weight plate (Olympic plates: 2.5, 5, 10, 25, 35 and 45 lb; 1.25, 2.5, 5, 10, 15, 20 and 25 kg), https://en.wikipedia.org/wiki/Weight_plate; IWF, Equipment (men’s bar 20 kg), https://iwf.sport/weightlifting_/equipment/"
    },
    {
      "given": {
        "unit": "lb",
        "w": 185,
        "bar": 45,
        "plb": [
          45,
          35,
          25,
          10,
          5,
          2.5
        ]
      },
      "expect": {
        "plates": "45, 25",
        "perSide": 70,
        "count": 2,
        "short": 0
      },
      "source": "hand calculation in content.mdx: (185 − 45) ÷ 2 = 70 = 45 + 25; Wikipedia, Weight plate (Olympic plates: 2.5, 5, 10, 25, 35 and 45 lb; 1.25, 2.5, 5, 10, 15, 20 and 25 kg), https://en.wikipedia.org/wiki/Weight_plate; IWF, Equipment (men’s bar 20 kg), https://iwf.sport/weightlifting_/equipment/"
    },
    {
      "given": {
        "unit": "lb",
        "w": 137,
        "bar": 45,
        "plb": [
          45,
          35,
          25,
          10,
          5,
          2.5
        ]
      },
      "expect": {
        "plates": "45",
        "perSide": 46,
        "count": 1,
        "loaded": 135,
        "short": 2
      },
      "source": "hand calculation in content.mdx: (137 − 45) ÷ 2 = 46; 45 leaves 1, smaller than 2.5, so 135 is loaded and 2 is short; Wikipedia, Weight plate (Olympic plates: 2.5, 5, 10, 25, 35 and 45 lb; 1.25, 2.5, 5, 10, 15, 20 and 25 kg), https://en.wikipedia.org/wiki/Weight_plate; IWF, Equipment (men’s bar 20 kg), https://iwf.sport/weightlifting_/equipment/"
    },
    {
      "given": {
        "unit": "kg",
        "wkg": 142.5,
        "barkg": 20,
        "pkg": [
          25,
          20,
          15,
          10,
          5,
          2.5,
          1.25
        ]
      },
      "expect": {
        "plates": "2 × 25, 10, 1.25",
        "perSide": 61.25,
        "count": 4,
        "loaded": 142.5,
        "short": 0
      },
      "source": "hand calculation in content.mdx: (142.5 − 20) ÷ 2 = 61.25 = 25 + 25 + 10 + 1.25; Wikipedia, Weight plate (Olympic plates: 2.5, 5, 10, 25, 35 and 45 lb; 1.25, 2.5, 5, 10, 15, 20 and 25 kg), https://en.wikipedia.org/wiki/Weight_plate; IWF, Equipment (men’s bar 20 kg), https://iwf.sport/weightlifting_/equipment/"
    },
    {
      "given": {
        "unit": "kg",
        "wkg": 20,
        "barkg": 20,
        "pkg": [
          25,
          20
        ]
      },
      "expect": {
        "plates": "none (the empty bar)",
        "perSide": 0,
        "count": 0,
        "loaded": 20,
        "short": 0
      },
      "source": "hand calculation in content.mdx: the target equals the bar, so no plates are loaded"
    }
  ],
  "sources": [
    "Wikipedia, Weight plate (Olympic plates: 2.5, 5, 10, 25, 35 and 45 lb; 1.25, 2.5, 5, 10, 15, 20 and 25 kg). https://en.wikipedia.org/wiki/Weight_plate (retrieved 2026-10-19)",
    "International Weightlifting Federation (IWF), Equipment: discs of 25 to 0.5 kg, men’s bar 20 kg, women’s bar 15 kg, collars 2.5 kg each. https://iwf.sport/weightlifting_/equipment/ (retrieved 2026-10-19)"
  ],
  "related": [
    "one-rep-max",
    "dots"
  ],
  "changelog": []
}