> For clean Markdown of any page, append .md to the page URL.
> For a complete documentation index, see https://docs.laposta.org/llms.txt.
> For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://docs.laposta.org/_mcp/server.

# How do date and time fields work in the API?

> The API uses two formats for dates and times. Read how to retrieve and send them.

The API returns dates and times in two formats, side by side in the same response:

* The standard format is `YYYY-MM-DD HH:MM:SS`, for example `2026-05-18 14:30:00`. This does not include a timezone. It represents the date and time in the timezone of the account. That timezone is specified in the `timezone` field of the same object.
* The ISO format includes the timezone offset, for example `2026-05-18T14:30:00+02:00`. You can recognise these fields by the `_iso` suffix.

```json
{
  "timezone": "Europe/Amsterdam",
  "modified": "2026-05-18 14:30:00",
  "modified_iso": "2026-05-18T14:30:00+02:00"
}
```

If you work with users or systems in different timezones, use the `_iso` variant. That way, it is always clear which timezone applies.

## Reading empty date fields

> **Warning**
>
> If the standard value is empty, the `_iso` variant may be completely absent from the response. For example, for a field that has never been modified, you will receive `"modified": null`, but no `modified_iso`. Therefore, do not assume that this field is always present in the response.

Other objects do return `"modified_iso": null` in the same situation. When reading the data, always check first whether the field is present in the response.

## Sending a date yourself

If an endpoint accepts a date, you can use either format. If you send an ISO date in a query string, replace the plus sign with `%2B`:

```text
event_date_from=2026-05-18T14:30:00%2B02:00
```

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