Setting Today's date as default for SP.FieldDateTime

Alistair Young 

Try using below code to create a date column with default value of today's date using SharePoint REST API:

var fieldEndpoint = _spPageContextInfo.webAbsoluteUrl + "/_api/web/lists/getByTitle('ListName')/fields";

$.ajax({
	url: fieldEndpoint,
	type: "POST",
	data: JSON.stringify({
		'__metadata': { 'type': 'SP.FieldDateTime' },
		'FieldTypeKind': 4,
		'Title': 'HandoffDate',
		'SchemaXml': '<Field Type="DateTime" DisplayName="Handoff Date" Name="HandoffDate" Required="FALSE" ID="{d6b835d3-820f-4926-85bd-7711cc31c4c8}" Format="DateTime"><Default>[today]</Default></Field>'
	}),
	headers: {
		"X-RequestDigest": $("#__REQUESTDIGEST").val(),
		"accept": "application/json;odata=verbose",
		"content-type": "application/json;odata=verbose"
	},
	success: function (data) {
		console.log("Field created successfully");
	},
	error: function (error) {
		console.log(error);
	}
});

Microsoft documentations: Fields REST API reference 

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