Online D&D5E Creature CR Estimator

DD 5E Creature CR calculator

DD 5E Creature CR calculator

This calculator is meant to be used by the DM (Dungeon Master) to fine tune custom creatures

I took some key creatures from the compendium, and estimated a metric (Difficulty) that can be translated into an estimated CR (Challenge Rating)

Difficulty is an integral metric of effective health against a range of attack bonus, multiplied by an integral metric of damage dealt across a range of AC, multiplied by a scaling factor that accounts for skills and attributes. It's a somewhat crude metric that seems to fit surprisingly well. Given that creature from the compendium can be more difficult or easier than their CR suggests.

Use it by loading a creature from the compendium, and tuning the fields to get a creature of the CR you desire for your encounter.

Distance UnitSelect the unit of distance used in the calculator

Meter [m] Square [sq] Feet [ft]

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Creature StatsCreature stats

Select Creature from CompendiumSelect the creature fro the compendium.

Zombie CR1/4 Goblin CR1/4 Hobgoblin CR1/2 Bugbear CR1 Ogre CR2 Bugbear Chief CR3 Hobgoblin Captain CR3 Triceratops CR5 T-Rex CR8 Roc CR11 Vampire Warrior CR15 Ancient Black Dragon CR21

Challenge Rating (CR)This creature can fight a party of four PC of level as CR. e.g. CR1/4 can fight 1 PC level 1. e.g. CR5 can fight four PC level 5

HealthThis creature can fight a party of four PC of level as CR. e.g. CR1/4 can fight 1 PC level 1. e.g. CR5 can fight four PC level 5

AC Armour ClassAC is the minimum roll to hit. It models evasion by either toughness or sneakiness.

Number of AttacksNumber of times the creature can attack in one turn

Attack BonusBonus to attack die, check against enemy AC

Attack DamageDamage inflicted if the attack connects

Skill ScoreHaving abilities act as difficulty multiplier. 1 points for each minor skills like conditional advantage. 2 point for each useful skills, like movement boosts. 3 points for each strong skills, like fire breath. Do not count skill that boost damage e.g. multi attack, include that in the damage stats

Legendary ActionsUsually 3 legendary action points that replenish at the start of the turn, and can be used at the end of another creature's turn to activate one of several legendary actions. Often damage, but can be utility and control as well.

SpeedSpeed in the unit of measure given that the creature can move in a turn. I am not modeling varying speed (e.g. flying/multiple form) so use the most common speed

STR - StrengthAttribute

DEX - DexterityAttribute

CON - ConstitutionAttribute

INT - IntelligenceAttribute

WIS - WisdomAttribute

CHA - CharismaAttribute

Attribute ScoreAttributes and Speed contribute to the overall ability score, that act as multiplier of the Difficulty

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Creature Estimated DifficultyFrom stats, estimate the difficulty and CR of the creature, this is to help tuning stats

Estimated CRFrom difficulty estimate the creature CR

TTK Time To KillHow many turns would it takes this creature to kill itself. It shows if the creature is a Damage dealer (short TTK), a Bruiser or a Tank (long TTK)

Integral HealthHealth displayed against attacks over bonuses from -5 to +15

Integral DamageDPS displayed against AC over bonuses from 5 to 25

DifficultyIntegral health by integral damage