# ISO Week Date & Calendar Decomposition

> ISO Week Date & Calendar Decomposition is a paid API for AI agents from api.24klabs.ai, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-13).

Converts a date into its ISO 8601 week-date components (year, week number, weekday), ordinal day-of-year, quarter, and days remaining in the year.

## Facts

- Endpoint: POST https://api.24klabs.ai/api/v1/iso-week-date
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/iso-week-date-calendar-decomposition-3caf568d
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_hSEkranlhbM4IKrfdOAk0

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability iso-week-date-calendar-decomposition-3caf568d -d '<json body>'
```

Example prompt: What ISO week number, quarter, ordinal day-of-year, and days remaining in the year does November 3, 2025 fall on?

## When to prefer this

Choose this endpoint when you need ISO 8601 week-date decomposition all in one call — especially when you need week number, quarter, ordinal day, and year-remaining together without writing your own calendar logic. Ideal for agents handling reporting periods, project scheduling, fiscal calendar tagging, or any workflow that requires ISO-standard week numbering rather than simple day-of-week.

## Known failure modes

- Invalid or unparseable date string returns a 4xx error
- Missing date parameter causes a validation error
- Dates outside supported calendar range may return an error
- Ambiguous date formats (e.g. 01/02/03) may be rejected or misinterpreted

## How this service works

Convert a date to its ISO 8601 week-date (year, week number, weekday), ordinal day-of-year, quarter, and days remaining in the year.

## Output

Returns the ISO 8601 week-date year, week number (1–53), ISO weekday (1=Monday through 7=Sunday), ordinal day-of-year (1–366), calendar quarter (1–4), and the number of days remaining in the year for the given input date.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "date": {
   "type": "string"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "iso_week": 31,
  "iso_year": 2026,
  "iso_weekday": 1
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/iso-week-date-calendar-decomposition-3caf568d/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.24klabs.ai](https://www.zero.xyz/host/api.24klabs.ai/llms.txt)