Every Microsoft Dynamics CRM developer has faced this problem: How to get the entity type code for your custom entity in JavaScript. If you need the entity type code for the current form there are several supported ways to get it. But when you want the entity type code for a different custom entity, you are in trouble. The SDK has no real solution for this, and hard-coding is no option as the numbers can change per deployment. Digging through the client side object model I found a nice, although still unsupported, treasure which works with CRM 2011 and up, including the latest installment: 2015 update 1.