Doom metrics
health and damage values, common sizes and dimensions for Doom maps
Below are some core gameplay values and numbers that are useful for level design in Doom / Doom 2.
However, keep in mind this is an action game with aiming and dodging -- so the actual damage and damage per second (DPS) will depend heavily on enemy behavior, available cover, height changes, enemy composition, etc.

MAP07 "Dead Simple" from Doom 2, by American McGee and Sandy Petersen
Doom uses a grid with power-of-two numbers (e.g. 8, 16, 32, 64, 128, 256...) and textures are designed to work in increments of 8, 16, or 32.
Doom's graphics were designed for a 16:10 aspect ratio stretched vertically by 20% with non-square pixels for a 4:3 display. Today, this results in a lot of its art assets to appear vertically "squished". It also distorts any attempt at a coherent real world scale for Doom, which we can guess at: 16 horizontal Doom units = 10 vertical Doom units = 1 foot = 0.6 meters.
Typical map structure | Width in units |
Hallway (very narrow), crate, teleport pad | 64 |
Hallway (narrow), big door, wall textures | 128 |
Small room | 256-512 |
Medium room | 512-1024 |
Large room | 1024-1536 |
Average map size from Doom 1, Episode 1 | ~4000 |
Maximum map size (recommended, minimal glitches) | 32767 (+/- 16384) |
Maximum map size (technical, buggy and unstable) | 65535 (+/- 32768) |
Maximum map size: to calculate distances, Doom uses 16-bit signed integers which have a maximum value of +/- 32767. However, if you actually built a map that stretched from -32767 to +32767 (across 65535 units!) and somehow tricked the engine into running it, then it would still break other distance calculations like a monster's line of sight, because a value of 65535 would overflow past +32767 to become 0. For best results, keep all map geometry within 16384 units of the (0, 0, 0) origin.
Doom randomly simulates damage values by rolling virtual dice with each hit. For the shotguns, there's an additional buckshot spread simulation where each pellet must connect with the hitbox for full damage.
The damage per second (DPS) is a rough estimate based on the fire rate multiplied by the average damage per shot.
Weapon | Type | Effective Range | Fire rate per second | Damage per shot | Damage per second (DPS) |
Fist | Melee | 0-32 | 2 punches | 2-20 | 22 |
Berserk Fist | Melee | 0-32 | 2 punches | 20-200 | 220 |
Chainsaw | Melee | 0-33 | 9 revolutions | 2-20 | 90 |
Pistol | Hitscan | 0-512? | 2.5 bullets | 5-15 | 25 |
Shotgun | Near | 0-192? | 1 shot (7 pellets) | 5-15 * 7 = 35-105 | 70 |
Super Shotgun | Close | 0-128? | 1 shot (20 pellets) | 5-15 * 20 = 100-300 | 150 |
Chaingun | Hitscan | 0-512? | 9 bullets | 5-15 | 90 |
Rocket Launcher | Mid / Long | 128-512? | 1 rocket (+ splash, 128 unit range) | 20-160 + 0-128 | 150 |
Plasma Gun | Mid | 0-384? | 12 cells | 5-40 | 270 |
BFG 9000 | Mid | 0-384? | 1 shot (+ 40 tracers, 1024 unit range) | 100-800 + 49-87 | ~1200 |
Most maps begin with players killing low health enemies with the pistol and shotgun. Eventually the player relies more on the chaingun, super shotgun, and rocket launcher, while occasionally switching to the plasma gun for tougher enemies.
The rocket launcher, plasma gun, and BFG are usually less effective at very long range because of the lag built into their projectiles' travel time. At long distances, a monster can move out of the way before getting hit. Doom's autoaiming and randomized monster movement also means it can be tricky to lead shots. You can balance long range encounters toward the player's favor by placing monsters on pillars with no cover, limiting their ability to dodge the player's projectiles.

Monsters can look in cardinal (N, E, S, W) and ordinal (NE, SE, SW, NW) directions, essentially in 45 degree increments. They have a 180 degree sight cone based on their initial facing, and can hear combat sounds based on areas bounded by linedefs set to block sound.
If set to "ambush" mode, monsters have a 360 degree sight cone and ignore sounds.
Minimum hallway size is given as
(monster width + 2) x (monster height + 2)
but in practice, your hallways should usually be much wider since monsters might "step" in larger increments, and monsters block other monsters. Narrow off-angle hallways will force monsters into slower zig-zag movements, because remember, they can only turn and move in 45 degree increments.Stairs are tricky for monsters. In general, steps with long depths and shallow rises are always more dependable. Step height must always be 24 units or less (or else the monster won't cross) and minimum step depth / maximum slope is proportional to the monster width. For example, for a step that is 24u high, a trooper requires a step that is 33u deep (35 degree rise, 2:3 ratio) while a demon is wider so it requires 51u deep (25 degrees, 1:2 ratio). If you want to see the bounding box calculations yourself, see the
PCheckPosition()
and PTryMove()
functions in p_map.c
of the Doom source code.To simplify building for monsters, we generally recommend:
- Minimum hallway size: 128 wide x 128 tall, mostly built orthogonally at 90 degree angles to align with the grid with occasional 45 degree angles.
- Stairway step size: 16 high x 64 deep (15 degree rise, 1:4 ratio) or 8 high x 32 deep.
Monsters will use melee attacks within 64 units of their target, though the Revenant will attempt to use a melee attack within 196 units even if the target is too far. If further than 64 units, then monsters with ranged attacks are more likely to use attack the closer they are to the player, up to a maximum distance of 2048 units. But the Arch-vile has a particularly dangerous ranged attack, so it will only attack within 896 units.
When hit, monsters have a random chance to be stunned in a pain state -- weapons with fast fire rates (chain gun, plasma gun) or multiple projectiles (shotgun, super shotgun) are particularly good at stunlocking monsters and interrupting their attacks.