ISO date-time clamp

iso-datetime-clamp · version 1.0.0 · Dates & times (UTC, ISO 8601) · free, no key needed

Clamp a strict UTC ISO-8601 datetime into an inclusive [min, max] range.

Use when you need to: iso datetime clamp · bound datetime to range · restrict utc datetime to min max.

Supported

• iso datetime clamp
• bound datetime to range
• restrict utc datetime to min max

Not supported

• leap seconds
• time zones
• offsets other than Z
• fractional seconds
• open ranges

Behavior

• datetime, min, and max must match YYYY-MM-DDTHH:MM:SSZ with zero-padded fields and a real proleptic Gregorian UTC civil time, years 0001-9999.
• min must not be after max on the UTC millisecond timeline, or the call is rejected.
• If datetime is before min, the result is min. If datetime is after max, the result is max. Otherwise the result is datetime unchanged.

Input

• datetime (string, required): min length 20; max length 20; pattern ^\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}Z$
• min (string, required): min length 20; max length 20; pattern ^\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}Z$
• max (string, required): min length 20; max length 20; pattern ^\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}Z$

Output

• datetime (string, required): min length 20; max length 20

Limits

• min year: 1
• max year: 9999

Example

Request input:

{
  "datetime": "2026-09-15T00:00:00Z",
  "min": "2026-09-15T08:00:00Z",
  "max": "2026-09-15T18:00:00Z"
}

Response:

{
  "result": {
    "datetime": "2026-09-15T08:00:00Z"
  }
}

How to call it

MCP

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

{
  "id": "iso-datetime-clamp",
  "version": "1.0.0",
  "input": {
    "datetime": "2026-09-15T00:00:00Z",
    "min": "2026-09-15T08:00:00Z",
    "max": "2026-09-15T18:00:00Z"
  }
}

HTTP (no key)

curl -X POST https://computefirst.net/v1/tools/iso-datetime-clamp/versions/1.0.0/execute \
  -H "Content-Type: application/json" \
  -d '{"datetime":"2026-09-15T00:00:00Z","min":"2026-09-15T08:00:00Z","max":"2026-09-15T18:00:00Z"}'

The machine-readable contract is at /v1/tools/iso-datetime-clamp/versions/1.0.0.

CLI

node cli.mjs run iso-datetime-clamp 1.0.0 --input input.json --base-url https://computefirst.net

Get the client at /clients/cli/.

Related tools

• ISO date clamp: Clamp a YYYY-MM-DD calendar date into an inclusive [min, max] range.
• ISO date-time add seconds: Add a signed whole-second delta to a strict UTC ISO-8601 datetime.
• ISO date-time truncate: Truncate a strict UTC ISO-8601 datetime toward UTC zero at day, hour, minute, or second.
• ISO date min max: Return the earliest and latest date in a non-empty array of YYYY-MM-DD calendar dates.
• ISO date-time compare: Compare two strict UTC ISO-8601 datetimes and return -1, 0, or 1.
• ISO date-time diff seconds: Return the signed whole-second difference between two strict UTC ISO-8601 datetimes.