ISO date range list

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

Enumerate the dates in an inclusive [start, end] range stepped by a whole number of days.

Use when you need to: iso date range list · enumerate dates between two dates · every nth day in range.

Supported

iso date range list
enumerate dates between two dates
every nth day in range

Not supported

calendar-unit steps (weeks, months)
timezones
descending output

Behavior

start and end are strict YYYY-MM-DD calendar dates with year 0001-9999. start must not be after end.
step_days is an optional JSON integer >= 1, default 1.
dates lists start, start+step_days, start+2*step_days, ... up to and including end only when it lands exactly on a step; it never exceeds end. At most 10000 dates are returned, or the call is rejected.

Input

start (string, required): min length 10; max length 10; pattern ^\d{4}-\d{2}-\d{2}$
end (string, required): min length 10; max length 10; pattern ^\d{4}-\d{2}-\d{2}$
step_days (integer, optional): min 1

Output

dates (array of string, required): each min length 10; each max length 10

Limits

year min: 1
year max: 9999
max items: 10000

Example

Request input:

{
  "start": "2026-09-01",
  "end": "2026-09-05"
}

Response:

{
  "result": {
    "dates": [
      "2026-09-01",
      "2026-09-02",
      "2026-09-03",
      "2026-09-04",
      "2026-09-05"
    ]
  }
}

How to call it

MCP

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

{
  "id": "iso-date-range-list",
  "version": "1.0.0",
  "input": {
    "start": "2026-09-01",
    "end": "2026-09-05"
  }
}

HTTP (no key)

curl -X POST https://computefirst.net/v1/tools/iso-date-range-list/versions/1.0.0/execute \
  -H "Content-Type: application/json" \
  -d '{"start":"2026-09-01","end":"2026-09-05"}'

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

CLI

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

Get the client at /clients/cli/.

ISO date weekday occurrences in range: List every date within an inclusive date range that falls on a given ISO weekday.
ISO date age: Compute the calendar-aware elapsed years, months, and days between a birth date and an as-of date.
ISO date business days count: Count the business days in an inclusive date range, skipping caller-supplied weekend weekdays and holidays.
ISO date range intersect: Compute the intersection of two inclusive [start, end] date ranges.
ISO date compare: Compare two YYYY-MM-DD calendar dates and return -1, 0, or 1.
ISO date day of year: Return the ordinal day number (1-366) of a YYYY-MM-DD date within its calendar year.