Retrieve Object Type Codes via WebAPI Url

To quickly retrieve the object type codes you can add the following URL part to your CRM instance URL:

/api/data/v8.2/EntityDefinitions?$select=LogicalName,ObjectTypeCode&$filter=ObjectTypeCode%20gt%209999

The output looks like this:

{
  "@odata.context":"https://orgname.crm4.dynamics.com/api/data/v8.2/$metadata#EntityDefinitions(LogicalName,ObjectTypeCode)","value":[
    {
      "LogicalName":"msdyn_quotebookingproduct","ObjectTypeCode":10076,"MetadataId":"eabdb23d-67d9-4c20-b72e-7358079a1afd"
    },{
      "LogicalName":"msdyn_requirementresourcepreference","ObjectTypeCode":10017,"MetadataId":"d63ce867-9bd1-45ee-aedc-459394bedf35"
    },{
      "LogicalName":"msdyn_rmareceiptproduct","ObjectTypeCode":10086,"MetadataId":"5b57cb66-3728-4987-8b95-ab78d5dfcf9a"
    },{
      "LogicalName":"audius_auspraegungsmerkmal","ObjectTypeCode":10153,"MetadataId":"7316e442-e883-e711-8113-e0071b6e64b1"
    },{
      "LogicalName":"msdyn_agreementsubstatus","ObjectTypeCode":10039,"MetadataId":"f6523ac8-a75c-42c3-8895-a332eb017241"
    },{
      "LogicalName":"msdyn_incidenttypeservice","ObjectTypeCode":10053,"MetadataId":"cbec0a75-621f-4a54-b4f8-c2015756b0b8"
    },{
      "LogicalName":"msdyn_paymentmethod","ObjectTypeCode":10065,"MetadataId":"871a2d4d-e21e-49d8-a26b-66a7c1325287"
    },{
    .
    .
    .
}