> For the complete documentation index, see [llms.txt](https://docs.bookinglayer.com/api/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.bookinglayer.com/api/input-formatting.md).

# Input formatting

This document focuses on the data you are going to send to the Bookinglayer API via POST/PUT/PATCH endpoints. It lists the formatting expected by the API as well as describes some custom data reused amongst endpoints.

## Formatting

#### Dates

Dates should always be sent in the `yyyy-mm-dd` format. December 20th 2023 would be sent as `2023-12-20`.

#### Times

Time should always be sent in the `HH:MM` format (zero-prefixed hours followed by a colon and then zero-prefixed minutes). Twelve hours and thirty five minutes would be sent as `12:35`.

#### Datetimes

Some fields contain combinations of date and time. These fields are marked with `datetime` types and expect the following format: `yyyy-mm-dd HH:MM:SS`. December 20th 2023 at nineteen hours, thirteen minutes and nine seconds would be sent as `2023-12-20 19:13:09`.

#### Numbers

Numbers are sent as floats. Most resource fields support precision of two decimals, with a few exceptions that are noted in their respective documentation pages.

#### Country codes

Whenever there is a need to specify some country Bookinglayer expects ISO 3166 Alpha-2 country codes. A list of all codes in available on the [ISO website](https://www.iso.org/obp/ui/#search), under the Alpha-2 column. 

Note that this format isn't used exclusively for countries, it can be used for other fields such as [Person](/api/core-resources/persons.md#the-person-object) nationalities or phone country codes.