{
  "slug": "anion-gap",
  "title": "Anion Gap Calculator",
  "heading": "Anion Gap Calculator",
  "category": "fitness-health",
  "url": "https://www.revenuelab.fyi/toolbox/anion-gap",
  "summary": "Serum anion gap with albumin correction and delta gap.",
  "description": "Compute the serum anion gap from a basic metabolic panel, correct it for hypoalbuminemia, and get the delta gap that helps distinguish mixed acid-base disorders.",
  "formula": "AG = Na − (Cl + HCO₃). Corrected AG adds 2.5 per g/dL albumin below 4.0.",
  "dateModified": "2026-09-30",
  "run_url": "https://www.revenuelab.fyi/api/public/calc?tool=anion-gap",
  "inputs": [
    {
      "id": "na",
      "label": "Sodium",
      "kind": "number",
      "hint": null,
      "default": 140,
      "unit": "mEq/L",
      "min": 100,
      "max": null
    },
    {
      "id": "cl",
      "label": "Chloride",
      "kind": "number",
      "hint": null,
      "default": 104,
      "unit": "mEq/L",
      "min": 60,
      "max": null
    },
    {
      "id": "hco3",
      "label": "Bicarbonate",
      "kind": "number",
      "hint": null,
      "default": 24,
      "unit": "mEq/L",
      "min": 2,
      "max": null
    },
    {
      "id": "alb",
      "label": "Albumin",
      "kind": "number",
      "hint": null,
      "default": 4,
      "unit": "g/dL",
      "min": 0.5,
      "max": null
    },
    {
      "id": "k",
      "label": "Potassium (optional)",
      "kind": "number",
      "hint": null,
      "default": 4,
      "unit": "mEq/L",
      "min": 0,
      "max": null
    }
  ],
  "outputs": [
    {
      "id": "ag",
      "label": "Anion gap (mEq/L)",
      "format": "decimal",
      "hint": null,
      "primary": true
    },
    {
      "id": "corrected",
      "label": "Albumin-corrected gap",
      "format": "decimal",
      "hint": null,
      "primary": false
    },
    {
      "id": "delta",
      "label": "Delta gap",
      "format": "decimal",
      "hint": null,
      "primary": false
    },
    {
      "id": "deltaRatio",
      "label": "Delta ratio",
      "format": "decimal",
      "hint": null,
      "primary": false
    },
    {
      "id": "withK",
      "label": "Gap including potassium",
      "format": "decimal",
      "hint": null,
      "primary": false
    }
  ],
  "worked_example": {
    "inputs": [
      "Sodium: 140 mEq/L",
      "Chloride: 104 mEq/L",
      "Bicarbonate: 24 mEq/L",
      "Albumin: 4 g/dL",
      "Potassium (optional): 4 mEq/L"
    ],
    "outputs": [
      "Anion gap (mEq/L): 12",
      "Albumin-corrected gap: 12",
      "Delta gap: 0",
      "Delta ratio: 0",
      "Gap including potassium: 16"
    ]
  },
  "how_to": {
    "title": "How to use this",
    "steps": [
      "Enter sodium (mEq/L).",
      "Enter chloride (mEq/L).",
      "Enter bicarbonate (mEq/L).",
      "Enter albumin (g/dL).",
      "Enter potassium (optional) (mEq/L).",
      "Read your anion gap (meq/l) 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": {
        "na": 100,
        "cl": 62,
        "hco3": 14,
        "alb": 2.4,
        "k": 2.4
      }
    },
    {
      "name": "Typical",
      "description": "Defaults — the most common real-world setup.",
      "values": {
        "na": 140,
        "cl": 104,
        "hco3": 24,
        "alb": 4,
        "k": 4
      }
    },
    {
      "name": "Ambitious",
      "description": "Higher-end numbers — what if things really pop?",
      "values": {
        "na": 224,
        "cl": 166,
        "hco3": 38,
        "alb": 6.4,
        "k": 6.4
      }
    }
  ],
  "limitations": [
    "Population formulas describe averages; individual bodies vary, especially at the extremes of height, age, or muscle mass.",
    "Results do not account for medical conditions, medication, or pregnancy.",
    "Use this as a directional reference, not a diagnosis — talk to a clinician before acting on it."
  ],
  "faq": [
    {
      "q": "What's a normal gap?",
      "a": "Roughly 8–12 mEq/L on modern analyzers when potassium is excluded. Always check your lab's reference range."
    },
    {
      "q": "Why correct for albumin?",
      "a": "Albumin is the largest unmeasured anion. Low albumin masks a real elevated-gap acidosis."
    }
  ],
  "related": [],
  "license": "CC-BY-4.0",
  "citation": "RevenueLab — Anion Gap Calculator (https://www.revenuelab.fyi/toolbox/anion-gap)"
}