{
  "slug": "ph-calculator",
  "title": "pH Calculator",
  "heading": "pH and pOH Calculator",
  "category": "math",
  "url": "https://www.revenuelab.fyi/toolbox/ph-calculator",
  "summary": "pH, pOH, and ion concentrations from either direction.",
  "description": "pH is the negative log of hydrogen-ion concentration. Enter molarity to get pH, or work back from pH to concentration.",
  "formula": "pH = −log₁₀[H⁺]; pH + pOH = 14",
  "dateModified": "2026-09-30",
  "run_url": "https://www.revenuelab.fyi/api/public/calc?tool=ph-calculator",
  "inputs": [
    {
      "id": "conc",
      "label": "[H⁺] concentration",
      "kind": "number",
      "hint": null,
      "default": 0.0001,
      "unit": "mol/L",
      "min": 1e-14,
      "max": null
    }
  ],
  "outputs": [
    {
      "id": "pH",
      "label": "pH",
      "format": "decimal",
      "hint": null,
      "primary": true
    },
    {
      "id": "pOH",
      "label": "pOH",
      "format": "decimal",
      "hint": null,
      "primary": false
    },
    {
      "id": "oh",
      "label": "[OH⁻] (mol/L)",
      "format": "decimal",
      "hint": null,
      "primary": false
    },
    {
      "id": "verdict",
      "label": "Classification",
      "format": "raw",
      "hint": null,
      "primary": false
    }
  ],
  "worked_example": {
    "inputs": [
      "[H⁺] concentration: 0.0001 mol/L"
    ],
    "outputs": [
      "pH: 4",
      "pOH: 10",
      "[OH⁻] (mol/L): 0.0000000001",
      "Classification: Acidic"
    ]
  },
  "how_to": {
    "title": "How to use this",
    "steps": [
      "Enter [h⁺] concentration (mol/L).",
      "Read your ph 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": {
        "conc": 0.00006
      }
    },
    {
      "name": "Typical",
      "description": "Defaults — the most common real-world setup.",
      "values": {
        "conc": 0.0001
      }
    },
    {
      "name": "Ambitious",
      "description": "Higher-end numbers — what if things really pop?",
      "values": {
        "conc": 0.00016
      }
    }
  ],
  "limitations": [
    "Results are rounded for display; the underlying calculation keeps full precision.",
    "Very large or very small inputs may hit floating-point limits in the browser.",
    "Inputs outside the accepted range are clamped rather than rejected."
  ],
  "faq": [
    {
      "q": "How does the ph and poh calculator work?",
      "a": "pH is the negative log of hydrogen-ion concentration. Enter molarity to get pH, or work back from pH to concentration. The underlying maths is: pH = −log₁₀[H⁺]; pH + pOH = 14"
    },
    {
      "q": "What do I need to enter?",
      "a": "Just one value: [h⁺] concentration. 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 ph 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. Results are rounded for display; the underlying calculation keeps full precision."
    },
    {
      "q": "Who is this tool for?",
      "a": "It's built for students, developers, and anyone who needs the answer right now without setting up a spreadsheet."
    }
  ],
  "related": [],
  "license": "CC-BY-4.0",
  "citation": "RevenueLab — pH Calculator (https://www.revenuelab.fyi/toolbox/ph-calculator)"
}