ISO date range contains

iso-date-range-contains · version 1.0.0 · Dates & times (UTC, ISO 8601) · free, no key needed

Test whether an inclusive [start, end] date range contains a given date.

Use when you need to: iso date range contains · is date within range · point in date range check.

Supported

iso date range contains
is date within range
point in date range check

Not supported

open ranges
timezones
range-contains-range (use iso-date-range-intersect)

Behavior

range is an inclusive [start, end] YYYY-MM-DD date range with year 0001-9999; start must not be after end.
date is a strict YYYY-MM-DD calendar date.
contains is true if range.start <= date <= range.end, false otherwise.

Input

range (object, required)
date (string, required): min length 10; max length 10; pattern ^\d{4}-\d{2}-\d{2}$

Output

contains (boolean, required)

Limits

year min: 1
year max: 9999

Example

Request input:

{
  "range": {
    "start": "2026-01-01",
    "end": "2026-01-31"
  },
  "date": "2026-01-15"
}

Response:

{
  "result": {
    "contains": true
  }
}

How to call it

MCP

Connect https://computefirst.net/mcp (setup), then call execute with:

{
  "id": "iso-date-range-contains",
  "version": "1.0.0",
  "input": {
    "range": {
      "start": "2026-01-01",
      "end": "2026-01-31"
    },
    "date": "2026-01-15"
  }
}

HTTP (no key)

curl -X POST https://computefirst.net/v1/tools/iso-date-range-contains/versions/1.0.0/execute \
  -H "Content-Type: application/json" \
  -d '{"range":{"start":"2026-01-01","end":"2026-01-31"},"date":"2026-01-15"}'

The machine-readable contract is at /v1/tools/iso-date-range-contains/versions/1.0.0.

CLI

node cli.mjs run iso-date-range-contains 1.0.0 --input input.json --base-url https://computefirst.net

Get the client at /clients/cli/.

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