{
  "capability_id": "electrical.current_divider",
  "tool_id": "current-divider",
  "engine": "current-divider",
  "calculation_version": "1.0.2",
  "generated_at": "2026-09-16T22:03:43.724Z",
  "engine_build": "2026-09-14",
  "test_count": 23,
  "passed": 23,
  "failed": 0,
  "tests_summary": {
    "golden": {
      "total": 5,
      "passed": 5
    },
    "boundary": {
      "total": 12,
      "passed": 12
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    "property": {
      "total": 6,
      "passed": 6
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  "engine_tested": true,
  "expert_reviewed": false,
  "internally_reviewed": true,
  "review_kind": "internal",
  "source_checked": true,
  "reviewed_by": "CalculatorX electrical review",
  "reviewer_role": "electrical-engineer",
  "last_reviewed": "2026-09-14",
  "expert_review": {
    "status": "not_applicable",
    "reviewer": null,
    "note": "Internal domain review completed; not a named external expert review.",
    "kind": "internal"
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  "internal_review": {
    "status": "approved",
    "reviewer": {
      "name": "CalculatorX electrical review",
      "role": "electrical-engineer"
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    "reviewed_at": "2026-09-14",
    "scope": [
      "formula",
      "input semantics",
      "assumptions",
      "limitations",
      "sources",
      "tests"
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    "kind": "internal"
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  "page": "https://www.calculatorx.com/calc/electric/current-divider",
  "api": "https://www.calculatorx.com/api/v1/calc/current-divider",
  "schema_input": "https://www.calculatorx.com/schemas/electrical.current_divider.input.json",
  "schema_output": "https://www.calculatorx.com/schemas/electrical.current_divider.output.json",
  "assumptions": [
    "Exactly two ideal resistive parallel branches; no additional branch or load",
    "DC / resistive; currents entered as non-negative magnitudes"
  ],
  "limitations": [
    "Exactly two ideal resistive parallel branches; no additional branch or load",
    "Currents are non-negative magnitudes",
    "Web UI is It+R1+R2 only",
    "API supported combinations: It+R1+R2, R1+R2+I1, R1+R2+I2, It+I1+R1, It+I1+R2",
    "It+I1+I2 is underdetermined → UNSUPPORTED_COMBINATION",
    "Inverse It+I1+R1/R2 requires 0 < I1 < It for a finite R>0; I1=0 or I1=It → CURRENT_SPLIT_INVALID",
    "It=0 and I1=0 with R1 or R2 is underdetermined → UNSUPPORTED_COMBINATION",
    "<3 inputs → NEEDS_THREE_INPUTS"
  ],
  "boundary_conditions": [
    "<3 inputs → NEEDS_THREE_INPUTS",
    "R≤0 → VALUE_MUST_BE_POSITIVE",
    "It+I1+I2 → UNSUPPORTED_COMBINATION (underdetermined)",
    "It+I1+R inverse: I1=0 or I1=It → CURRENT_SPLIT_INVALID (no finite R>0)",
    "It=0 and I1=0 with R1 or R2 → UNSUPPORTED_COMBINATION (degenerate)"
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    {
      "title": "IEC 60050 — International Electrotechnical Vocabulary",
      "section": "Kirchhoff law for nodes (IEV 131-15-09)",
      "url": "https://www.electropedia.org/iev/iev.nsf/display?openform&ievref=131-15-09",
      "supports": "Algebraic sum of currents at a node is zero; I1 + I2 = It for two parallel branches",
      "kind": "standard",
      "accessed": "2026-09-12",
      "clause": "IEV 131-15-09"
    },
    {
      "title": "IEC 60050 — International Electrotechnical Vocabulary",
      "section": "Resistance (IEV 131-12-04)",
      "url": "https://www.electropedia.org/iev/iev.nsf/display?openform&ievref=131-12-04",
      "supports": "R = u/I on each branch; common node voltage V = I1·R1 = I2·R2",
      "kind": "standard",
      "accessed": "2026-09-12",
      "clause": "IEV 131-12-04"
    },
    {
      "title": "Horowitz & Hill — The Art of Electronics",
      "section": "3rd ed., Cambridge University Press, 2015 — Chapter 1 Foundations, current dividers",
      "supports": "Two-branch inverse-R current split",
      "kind": "reference",
      "publisher": "Cambridge University Press",
      "published": "2015"
    }
  ],
  "methods": [
    "Kirchhoff's current law (KCL): I1 + I2 = It",
    "Ohm's law: V = I1·R1 = I2·R2"
  ],
  "fingerprint": "sha256:503e9a018cc00a1ca3c8546171a4ed84c28bbf686f0cc7b955d00d3e1ca1bcdc",
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      "ok": true,
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        "R1": 100,
        "R2": 200
      },
      "expect": {
        "I1": 0.02,
        "I2": 0.01,
        "V": 2
      },
      "expectWarning": null,
      "actual": {
        "It": 0.03,
        "R1": 100,
        "R2": 200,
        "I1": 0.02,
        "I2": 0.01,
        "V": 2
      },
      "tol": 1e-12
    },
    {
      "id": "needs-three",
      "ok": true,
      "kind": "boundary",
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        "It": 0.03,
        "R1": 100
      },
      "expectError": "NEEDS_THREE_INPUTS",
      "code": "NEEDS_THREE_INPUTS",
      "error": "currentDivider needs a solvable three-value combination of It,R1,R2,I1,I2"
    },
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      "id": "zero-R",
      "ok": true,
      "kind": "boundary",
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        "R1": 0,
        "R2": 100
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      "code": "VALUE_MUST_BE_POSITIVE",
      "error": "R1 must be greater than zero"
    },
    {
      "id": "solve-from-I1",
      "ok": true,
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        "I1": 0.02
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        "R2": 200,
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        "I2": 0.009999999999999998,
        "V": 2
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        "I2": 0.01
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        "R1": 100,
        "R2": 200,
        "I1": 0.019999999999999997,
        "I2": 0.01,
        "V": 1.9999999999999998
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      "tol": 1e-12
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        "V": 2
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        "I2": 0.009999999999999998,
        "V": 1.9999999999999998
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      "tol": 1e-12
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      "code": "CURRENT_SPLIT_INVALID",
      "error": "inverse resistance requires 0 < I1 < It (finite R>0)"
    },
    {
      "id": "inverse-i1-eq-It-R1",
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      "code": "UNSUPPORTED_COMBINATION",
      "error": "It=0 and I1=0 cannot uniquely determine the other resistance"
    },
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      "error": "It=0 and I1=0 cannot uniquely determine the other resistance"
    },
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