Date Difference Calculator API

Time between two dates in years, months and days, plus total days, weeks and business days (Monday–Friday).

POST /api/v1/tools/date-difference-calculatorMCP date_difference_calculatorTime & Date

Count the days between two dates, as years, months and days, total days and weeks, plus business days (Monday to Friday). Leap years handled.

Input

Send these as a JSON object. Unknown fields are rejected.

start: Start date as YYYY-MM-DD. (string, up to 10 characters, required)
end: End date as YYYY-MM-DD. If it's before start the dates are swapped and reversed is true. (string, up to 10 characters, required)
includeEnd: Count the end date as one more day (by default the start date counts and the end date doesn't, like counting nights). (boolean, default false)

Try it in the browser JSON Schema Get an API key

curl https://pithlab.com/api/v1/tools/date-difference-calculator \n  -H "Authorization: Bearer $PITHLAB_KEY" \n  -H "Content-Type: application/json" \n  -d '{"start":"2026-01-15","end":"2026-10-20"}'

Example response

{
  "ok": true,
  "result": {
    "start": "2026-01-15",
    "end": "2026-10-20",
    "reversed": false,
    "years": 0,
    "months": 9,
    "days": 5,
    "totalMonths": 9,
    "totalDays": 278,
    "weeks": 39,
    "remainderDays": 5,
    "businessDays": 198,
    "text": "From 2026-01-15 to 2026-10-20: 9 months, 5 days (278 days, 198 business days)"
  }
}