DnD Resource of the Week: Challenge Rating Calculator by Leugren

Image of mind flayer from Dungeons and Dragons

When brewing anything. but especially something my players are going to have to face on a somewhat even footing,–something that can kill them–balance is always an issue. Within reason, a “broken” class, weapon or magic spell is less likely to annoy the table  than a monster that one-hit kills the heroes without giving them a chance in The Nine Hells to fight back. Elements of a frustrating enemy can include:

  • One hit kills (I already mentioned this)
  • One-hit perma death (even worse)
  • AC or damage resistances that make injuring an enemy impossible (especially if the enemy takes a while to kill you)
  • Attributes that stop the players doing anything

Two Mind Flayers from Dungeons and Dragons


Balance is an element of design that I struggle with regularly, and I often have to post my creations on a site like reddit for feedback. It helps if you’re a math whiz who can quickly calculate all statistical outcomes and amend CR as necessary. But I am most certainly not a math whiz. Of course, this is where play testing comes in, but it’s nice to have some guidance  before you bring a beast to the table; that way you can focus on detail, flavor and narrative potential.

None of this is to say that you can’t include extremely challenging, or even near-impossible foes. But you should probably do so rarely, leaving such encounters for moments of high drama, when their impact is most significant.

This week’s DnD resource will help you create more balanced monsters before the play-testing phase. It’s

D&D 5E Tools by Leugren: Quick Monster CR Calculator

It achieves pretty much what the title suggests. You put in Average Hit Points, Armor Class, Average Damage Per Round (see the Dungeon Master’s Guide for info on how to calculate this), Attack Type (does it go against the AC or rely on a saving throw), and the save DC itself. Plug those in and hit calculate and you have your CR.

.Dnd 5e Tools


Is it perfect? No. Should you do the rest of the leg work yourself? Yes. Does it mean you don’t have to play test? Of course not. But it’s a good indication that you’re on the right track.