Date Fields
A structured input that stores date values as ISO 8601 timestamps. Editors pick the date from a calendar, and can pick a time as well when you set ui.timeFormat.
Type Definition
For additional properties common to all Field types, check the Field type definition.
Set this to "datetime" to use the Datetime Field.
The name of the field for internal use.
All properties marked as REQUIRED must be specified for the field to work properly.
TinaCMS converts the picked date from the editor's local time and saves it in UTC.
Examples
Simple field
Field with custom date format
Set ui.dateFormat to change how TinaCMS shows the date to editors. TinaCMS still saves the full timestamp, such as 2026-10-09T00:00:00.000Z.
Field that saves only the date
A datetime field always saves a full timestamp. TinaCMS turns the value back into a date before it writes the file, even when ui.parse returns a bare date.
To save a bare YYYY-MM-DD, use a string field with the date component:
parse receives the picked date as an ISO string and saves the day the editor picked, in their local time. format reads a stored 2026-10-09 as local midnight. Without it, the picker reads that value as midnight UTC, and editors west of UTC see October 8.
GraphQL treats this field as a string, so your queries can't use the after and before filters that datetime fields support.
If you switch an existing datetime field to this, quote each value in your files first, for example date: '2026-10-09'. YAML reads an unquoted date as a date rather than a string, and indexing then fails with Unable to seed for that file.
Field including time picker
You can add a timepicker to the date UI by supplying the ui.timeFormat property.