{
  "schemaVersion": "1.0",
  "id": "https://elect-learn.org/en/tools/ohms-law-calculator/",
  "url": "https://elect-learn.org/en/tools/ohms-law-calculator/",
  "markdownUrl": "https://elect-learn.org/en/tools/ohms-law-calculator/index.md",
  "jsonUrl": "https://elect-learn.org/en/tools/ohms-law-calculator/index.json",
  "language": "en",
  "title": "Ohm's Law Calculator",
  "description": "Enter any two positive values to calculate voltage, current, resistance, and power for an ideal DC resistive circuit. Free in-browser tool; not for installation sizing.",
  "kind": "calculator",
  "safetyNotice": "Learning reference only: electrical codes, permits, inspection bodies, and licensing rules differ by region. This course is not a substitute for local code, licensed training, permits, or authority requirements. Before any hands-on work, de-energize, verify absence of voltage, and follow local regulators/AHJ and employer procedures.",
  "sections": [
    {
      "id": "ohms-law-formulas",
      "heading": "What this Ohm's law calculator solves",
      "paragraphs": [
        "For an ideal DC resistive model, Ohm's law relates voltage, current and resistance as V = I × R. Electrical power is related as P = V × I. Enter any two positive values and the calculator derives the remaining two."
      ],
      "items": [
        "Voltage and current: R = V ÷ I; P = V × I.",
        "Voltage and resistance: I = V ÷ R; P = V² ÷ R.",
        "Voltage and power: I = P ÷ V; R = V² ÷ P.",
        "Current and resistance: V = I × R; P = I² × R.",
        "Current and power: V = P ÷ I; R = P ÷ I².",
        "Resistance and power: I = √(P ÷ R); V = √(P × R)."
      ]
    },
    {
      "id": "calculator-example",
      "heading": "Example: 12 V across 6 Ω",
      "paragraphs": [
        "Enter voltage = 12 V and resistance = 6 Ω. The ideal calculation gives current = 2 A and power = 24 W. The result describes this mathematical model only; it does not select a real component or prove that a circuit is safe."
      ],
      "links": [
        {
          "title": "Learn voltage, current, resistance, and power",
          "url": "https://elect-learn.org/en/lesson/04-voltage-current-power/"
        },
        {
          "title": "Practise series and parallel circuit reasoning",
          "url": "https://elect-learn.org/en/lesson/06-series-parallel-voltage-drop/"
        }
      ]
    },
    {
      "id": "calculator-scope",
      "heading": "Scope and safety boundary",
      "paragraphs": [
        "Use this page for positive-value paper exercises involving an ideal DC resistive load. It does not model AC phase angle, power factor, reactance, motor starting, voltage drop, temperature, conductor ampacity, installation method, fault current, protective-device behavior or local code.",
        "Never use this calculator to choose wire size, breaker, fuse, equipment rating or authorize electrical work. Real measurements and energized work require suitable instruments, procedures, authorization and task-specific competence."
      ]
    },
    {
      "id": "calculator-sources",
      "heading": "Formula sources and editorial status",
      "paragraphs": [
        "The formula relationships were checked against US government references on 28 October 2026. This page has not received an independent professional review; the linked sources support the basic relationships, not a site-specific design decision."
      ],
      "links": [
        {
          "title": "NIST — Ampere: The Present",
          "url": "https://www.nist.gov/si-redefinition/ampere/ampere-present"
        },
        {
          "title": "US Department of Energy — Electrical Systems and Safety Oversight Guide",
          "url": "https://www.energy.gov/documents/qsr-electricalsafetysystemspdf"
        },
        {
          "title": "Content responsibility and review status",
          "url": "https://elect-learn.org/en/methodology/"
        }
      ]
    }
  ],
  "dateModified": "2026-10-28",
  "datePublished": "2026-10-28",
  "publisher": {
    "name": "Elect Learn",
    "url": "https://elect-learn.org"
  },
  "review": {
    "status": "not-independently-reviewed",
    "statement": "No independent professional review is recorded. Cited sources do not imply review or endorsement by those organizations.",
    "policyUrl": "https://elect-learn.org/en/methodology/"
  }
}