In the most recent release of minecraft (1.13) the explosion radius have slightly increased in overall for all the entities that explode. 

I attach two worlds where you can see clearly in comparison between 1.12 and 1.13 the difference between explosion. 

As an example, and where its more visible, powered creepers (and end crystals) used to make an explosion of radius 10 , but this have increased to 11/12 (not able to test precisely) But presumably, vanilla values have not changed for the entities (creepers still have the same explosion radius as in 1.12) but again, not able to check in other entities such as the wither boss, tnt, minecart with tnt or end crystal.