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Sometimes, you would need List or Library GUID to use that in some operation. In such cases, how do you get hold of GUID using REST API? There is a straight-forward end point which you can use: /_api/web/lists/getByTitle('ListTitle')/Id This will return the GUID of a List or Library. There is also another approach. However this approach works only if a List or Library contains at least one item. /_api/web/lists/getByTitle('ListTitle')/items This is a familiar end point which we use to fetch items of a List or Library. To get the GUID from the response, you would do: var listIDTemp = response.data.d.results.__metadata.id; var listID = listIDTemp.substring(listIDTemp.lastIndexOf("guid") + 5).split('\''); As you can see, we are doing string operations to fetch GUID from metadata.id. This contains information only if the response has at least one item.