Both are right, but comfy is more informal. It's just used to place emphasis on. Comfortable is the state of comfort.
This bed was designed to provide comfort to its. Comfortable 的同義字@slato they both mean comfortable, but comfy is a cute informal way to say it this bed is comfortable. Comfy的同義字@sushimasters the best way to understand this is to imagine a very comfortable bed.
Q&a about usage, example sentences, meaning and synonyms of word comfy. The soft mattress makes it comfy the warm blankets make it cozy|@sushimasters the.