I came across this today from one of my favourite gaming sites (Blog of Holding). It’s a wonderful resource for generating random encounters in D&D 5e (or in just about any rpg, really).
As the author states, running random encounters straight out of the Dungeon Master’s Guide can be a bit cumbersome (I know this from 1st-hand experience). This can help streamline the process.
Anyway, I won’t talk about it anymore because the author explains it perfectly well on his blog post. Check it out, I strongly recommend it (and I’ll be using it in my current campaign).