{
  "slug": "guitar-string-tension",
  "title": "Guitar String Tension Calculator",
  "heading": "Guitar String Tension Calculator",
  "category": "other",
  "url": "https://www.revenuelab.fyi/toolbox/guitar-string-tension",
  "summary": "String tension from gauge, scale length, and pitch.",
  "description": "Changing tunings or scale length shifts tension hard. This estimates pounds of tension per string.",
  "formula": "T = (UW × (2 × L × F)²) ÷ 386.4",
  "dateModified": "2026-09-30",
  "run_url": "https://www.revenuelab.fyi/api/public/calc?tool=guitar-string-tension",
  "inputs": [
    {
      "id": "gauge",
      "label": "String gauge",
      "kind": "number",
      "hint": null,
      "default": 0.046,
      "unit": "in",
      "min": null,
      "max": null
    },
    {
      "id": "scale",
      "label": "Scale length",
      "kind": "number",
      "hint": null,
      "default": 25.5,
      "unit": "in",
      "min": null,
      "max": null
    },
    {
      "id": "freq",
      "label": "Target pitch",
      "kind": "number",
      "hint": null,
      "default": 82.41,
      "unit": "Hz",
      "min": null,
      "max": null
    },
    {
      "id": "density",
      "label": "Unit weight",
      "kind": "number",
      "hint": null,
      "default": 0.0000323,
      "unit": "lb/in",
      "min": null,
      "max": null
    }
  ],
  "outputs": [
    {
      "id": "tension",
      "label": "Tension (lb)",
      "format": "decimal",
      "hint": null,
      "primary": true
    },
    {
      "id": "kg",
      "label": "Tension (kg)",
      "format": "decimal",
      "hint": null,
      "primary": false
    },
    {
      "id": "freq",
      "label": "Pitch (Hz)",
      "format": "decimal",
      "hint": null,
      "primary": false
    },
    {
      "id": "scale",
      "label": "Scale length (in)",
      "format": "decimal",
      "hint": null,
      "primary": false
    }
  ],
  "worked_example": {
    "inputs": [
      "String gauge: 0.046 in",
      "Scale length: 25.5 in",
      "Target pitch: 82.41 Hz",
      "Unit weight: 0.0000323 lb/in"
    ],
    "outputs": [
      "Tension (lb): 1.48",
      "Tension (kg): 0.67",
      "Pitch (Hz): 82.41",
      "Scale length (in): 25.5"
    ]
  },
  "how_to": {
    "title": "How to use this",
    "steps": [
      "Enter string gauge (in).",
      "Enter scale length (in).",
      "Enter target pitch (Hz).",
      "Enter unit weight (lb/in).",
      "Read your tension (lb) on the right — it updates as you type.",
      "Hit Share to keep the scenario or send it to someone."
    ]
  },
  "scenarios": [
    {
      "name": "Conservative",
      "description": "Lower-end numbers — what if things land soft?",
      "values": {
        "gauge": 0.0276,
        "scale": 15.299999999999999,
        "freq": 49.446,
        "density": 0.000019379999999999997
      }
    },
    {
      "name": "Typical",
      "description": "Defaults — the most common real-world setup.",
      "values": {
        "gauge": 0.046,
        "scale": 25.5,
        "freq": 82.41,
        "density": 0.0000323
      }
    },
    {
      "name": "Ambitious",
      "description": "Higher-end numbers — what if things really pop?",
      "values": {
        "gauge": 0.0736,
        "scale": 40.800000000000004,
        "freq": 131.856,
        "density": 0.00005168
      }
    }
  ],
  "limitations": [
    "Estimates assume standard, average conditions — local rules, pricing, and materials vary.",
    "Results are rounded for readability; add a buffer before ordering, booking, or committing.",
    "Double-check anything with a real cost attached against a local quote."
  ],
  "faq": [
    {
      "q": "How does the guitar string tension calculator work?",
      "a": "Changing tunings or scale length shifts tension hard. This estimates pounds of tension per string. The underlying maths is: T = (UW × (2 × L × F)²) ÷ 386.4"
    },
    {
      "q": "What do I need to enter?",
      "a": "4 values: string gauge, scale length, target pitch, and unit weight. Each field starts with a sensible default, so you can change one number at a time and watch the result move."
    },
    {
      "q": "What does the tension (lb) result mean?",
      "a": "It is returned as a decimal number and updates live as you edit the inputs, so you can compare two or three versions of a scenario in a few seconds."
    },
    {
      "q": "Is this calculator free, and do I need an account?",
      "a": "Yes, it's free, and no account is required. Nothing you type is stored on our servers — the maths runs entirely in your browser."
    },
    {
      "q": "How accurate is the result?",
      "a": "It applies the standard formula exactly, so the arithmetic is precise. Estimates assume standard, average conditions — local rules, pricing, and materials vary."
    },
    {
      "q": "Who is this tool for?",
      "a": "It's built for anyone doing everyday planning maths — a quick estimate that would otherwise need four browser tabs and a calculator app."
    }
  ],
  "related": [
    "https://www.revenuelab.fyi/toolbox/model-railroad-scale"
  ],
  "license": "CC-BY-4.0",
  "citation": "RevenueLab — Guitar String Tension Calculator (https://www.revenuelab.fyi/toolbox/guitar-string-tension)"
}