{
  "slug": "days-between-dates",
  "title": "Days Between Dates Calculator",
  "heading": "Days Between Dates Calculator",
  "category": "other",
  "url": "https://www.revenuelab.fyi/toolbox/days-between-dates",
  "summary": "Exact days, weeks, weekdays, and months between two dates.",
  "description": "Calendar math is deceptively easy to get wrong because of leap years and month lengths. This counts the exact elapsed days and breaks out business days separately.",
  "formula": "Days = (End − Start) ÷ 86,400,000 milliseconds.",
  "dateModified": "2026-09-30",
  "run_url": "https://www.revenuelab.fyi/api/public/calc?tool=days-between-dates",
  "inputs": [
    {
      "id": "start",
      "label": "Start date",
      "kind": "date",
      "hint": null,
      "default": null
    },
    {
      "id": "end",
      "label": "End date",
      "kind": "date",
      "hint": null,
      "default": null
    }
  ],
  "outputs": [
    {
      "id": "days",
      "label": "Total days",
      "format": "number",
      "hint": null,
      "primary": true
    },
    {
      "id": "business",
      "label": "Business days",
      "format": "number",
      "hint": null,
      "primary": false
    },
    {
      "id": "weeks",
      "label": "Weeks",
      "format": "decimal",
      "hint": null,
      "primary": false
    },
    {
      "id": "weekends",
      "label": "Weekend days",
      "format": "number",
      "hint": null,
      "primary": false
    },
    {
      "id": "months",
      "label": "Approximate months",
      "format": "decimal",
      "hint": null,
      "primary": false
    },
    {
      "id": "years",
      "label": "Approximate years",
      "format": "decimal",
      "hint": null,
      "primary": false
    }
  ],
  "worked_example": {
    "inputs": [
      "Start date: 2026-09-30",
      "End date: 2026-09-30"
    ],
    "outputs": [
      "Total days: 0",
      "Business days: 0",
      "Weeks: 0",
      "Weekend days: 0",
      "Approximate months: 0",
      "Approximate years: 0"
    ]
  },
  "how_to": {
    "title": "How to use this",
    "steps": [
      "Enter start date.",
      "Enter end date.",
      "Read your total days 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": {
        "start": "2026-09-30",
        "end": "2026-09-30"
      }
    },
    {
      "name": "Typical",
      "description": "Defaults — the most common real-world setup.",
      "values": {
        "start": "2026-09-30",
        "end": "2026-09-30"
      }
    },
    {
      "name": "Ambitious",
      "description": "Higher-end numbers — what if things really pop?",
      "values": {
        "start": "2026-09-30",
        "end": "2026-09-30"
      }
    }
  ],
  "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 days between dates calculator work?",
      "a": "Calendar math is deceptively easy to get wrong because of leap years and month lengths. This counts the exact elapsed days and breaks out business days separately. The underlying maths is: Days = (End − Start) ÷ 86,400,000 milliseconds."
    },
    {
      "q": "What do I need to enter?",
      "a": "2 values: start date, and end date. 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 total days result mean?",
      "a": "It is returned as a whole 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/add-days-to-date",
    "https://www.revenuelab.fyi/toolbox/business-days",
    "https://www.revenuelab.fyi/toolbox/age-calculator"
  ],
  "license": "CC-BY-4.0",
  "citation": "RevenueLab — Days Between Dates Calculator (https://www.revenuelab.fyi/toolbox/days-between-dates)"
}