[**hijri-core v1.0.1**](../README.md) *** [hijri-core](../README.md) / ConversionOptions # Interface: ConversionOptions Defined in: [types.ts:57](https://github.com/acamarata/hijri-core/blob/94bc28ebc35ae2f3cb39db5be34561152a5b899d/src/types.ts#L57) Options accepted by the convenience conversion functions. Omitting `calendar` defaults to `'uaq'` (Umm al-Qura). Pass any name previously given to [registerCalendar](../functions/registerCalendar.md) to use a custom engine. ## Properties ### calendar? > `optional` **calendar?**: `string` Defined in: [types.ts:58](https://github.com/acamarata/hijri-core/blob/94bc28ebc35ae2f3cb39db5be34561152a5b899d/src/types.ts#L58)