Critical Chance

Critical Chance is a derived statistic in Fallout, Fallout 2, Fallout 3, Fallout Tactics and Fallout: Brotherhood of Steel.

Fallout, Fallout 2 and Fallout Tactics
The chance to cause a critical hit in combat is increased by this amount. An Aimed Shot has a higher chance to score a critical hit than an unaimed shot. In Fallout Tactics, the Science skill also apparently has an effect on critical chance against robotic enemies.


 * $$\text{Initial level}=\text{Luck}\times1\%$$


 * The Finesse trait increases the critical chance by 10%.
 * The More Criticals perk increases the critical chance by 5% per rank.
 * The Sniper perk increases the critical chance to 10*Luck for ranged weapons.
 * The Slayer perk increases the critical chance to 100% for melee weapons.

Base Chance
Luck in the main base factor that determines the chances of a critical strike on a opponent.


 * $$\text{Initial level}=\text{Luck}\times1\%$$

Example: A starting Luck of 5.


 * $$5\times 1=5\%~(\text{Base chance})$$

Notes:
 * Maximum initial base is capped at 10%.
 * Ninja perk can increase this limit by another +15% for Melee and Unarmed weapons.
 * Finesse perk can increase this limit by another +5%.
 * Survival Expert perk can increase this limit by another +3%.
 * Strikes dealt in V.A.T.S have additional +15% critical chance added.
 * Some weapons have 0% chance of a critical strike (see Critical Multiplier for detail of effects).

Critical Multiplier
All weapons have a critical multiplier that modifies the player's base critical chance to create a new percentage to score a critical hit. This may improve or hinder the player's ability to score a critical hit depending on the weapons Critical multiplier.


 * $$\text{Base chance}\times\text{Critical multiplier}$$

Example: A starting Luck of 5 and using a Sniper Rifle.


 * $$5\times 1=5\%~(\text{Base chance})\times5=25\%~(\text{Critical multiplier})$$

Notes
 * The critical multiplier for fully automatic weapons is much lower than for single-shot weapons.
 * There are a few weapons that have a x 0 multiplier, which makes it impossible to score a critical hit
 * For a detailed list of weapon critical multipliers see Fallout 3 weapons.

Weapon Condition
The final critical chance is also modified by weapon condition.


 * $$\mbox{Base chance} \times \mbox{Critical multiplier} \times \mbox{Condition}$$

For example, a character with 5 Luck and using a Sniper Rifle in 50% condition would have,


 * $$5\times 1=5\%~(\text{Base chance})\times5=25\%~(\text{Critical multiplier})\times50\%~(\text{Condition})=12.5\%~\text{Critical chance}$$

Fallout: New Vegas
The formulas for critical chance seem unchanged from Fallout 3. You receive 1% of critical chance for each point placed into Luck. At character creation you can add an additional 3% for all weapons by choosing the Built to Destroy trait.


 * Attributes, perks and traits that increase critical chance include:
 * Luck (permanent +1-10%)
 * Built to Destroy (permanent +3%)
 * Finesse (permanent +5%)
 * Ninja (permanent +15% for melee and unarmed weapons)
 * Laser Commander (permanent +10% with lasers).
 * Set Lasers for Fun (permanent +2/4% with lasers)
 * Meat of Champions (temporary +1 Luck when eating a fresh corpse)
 * Intense Training (permanent +1 Luck if selected)


 * Items that increase critical chance -
 * 1st Recon beret (temporary +5%)
 * Naughty Nightwear (temporary +1 Luck)
 * True Police Stories (temporary +5 or 10% critical hit chance with Comprehension)

Prior to weapon multipliers.
 * This means you can raise your critical chance to -
 * 33% for Guns, Explosives and non-laser Energy Weapons.
 * 47% for laser Energy Weapons.
 * 48% for Melee Weapons and Unarmed Note: The 15% critical chance for the Ninja perk may not apply as it should, see the bugs section on the Ninja page for more details.

Weapons capable of 90-100% critical hit chance

 * These statistics assume the player has 10 Luck, Finesse, Ninja, Built to Destroy, a 1st Recon Beret, and has recently consumed a True Police Stories with Comprehension. However, they do NOT count in the extra 5% critical one would achieve in VATS. Though one would assume a PC would use VATS far more often than they would consume a True Police Stories . Also a chance of 100% can and usually does mean the actual chance is above 100%.
 * Guns
 * Sniper rifle (100%)
 * Gobi Campaign scout rifle (100%)
 * Ratslayer (100%)


 * Energy Weapons
 * Pew Pew (100%)
 * AER14 prototype (94%)
 * Alien Blaster (100%)
 * Incinerator (100%)
 * Heavy Incinerator (100%)
 * Flamer (100%)


 * Melee
 * Shovel (100%)
 * Combat Knife (96%)
 * Chance's knife (96%)
 * Broad machete (96%)
 * Liberator (100%)
 * Straight razor (96%)
 * Figaro (100%)
 * Shishkebab (96%)
 * Switchblade (96%)
 * Cattle prod (96%)


 * Unarmed
 * Bladed gauntlet (96%)
 * Cram Opener (96%)
 * Golden Gloves (96%)
 * Mantis gauntlet (100%)

Weapons capable of 50-89% critical hit chance

 * Guns
 * Lucky (82.5%)
 * Maria (66%)
 * That Gun (82.5)


 * Energy Weapons
 * Gauss Rifle (66%)
 * YCS/186 (66%)
 * Plasma rifle (66%)
 * Van Graff plasma rifle (66%)
 * Laser rifle (70.5%)
 * Van Graff laser rifle (70.5%)
 * Laser pistol (70.5%)
 * Q-35 Matter Modulator (66%)
 * Tesla cannon (66%)
 * Tesla-Beaton prototype (66%)
 * Tri-beam laser rifle (70.5%)


 * Melee
 * Machete (72%)
 * Machete gladius (72%)
 * Nephi's Golf Driver (57.6%)

Weapons capable of 39.5-49.5% critical hit chance

 * Guns
 * Ranger Sequoia (49.5%)
 * Abilene Kid LE BB Gun (49.5%)
 * Cowboy Repeater (41.25%)
 * La Longue Carabine (49.5%)


 * Energy Weapons
 * Plasma pistol (49.5%)
 * Recharger pistol (39.6%)
 * Recharger rifle (49.5%)
 * Gatling laser (47%)


 * Melee
 * Any Melee Weapons with a neutral (x1.0) critical multiplier. (48%)


 * Unarmed
 * Any Unarmed Weapons with a neutral (x1.0) critical multiplier. (48%)

Fallout: Brotherhood of Steel
In Fallout: Brotherhood of Steel, a critical hit allows to exceed the maximum limit of damage for a weapon.

Some weapons are very powerful with a high critical chance, such as the Double-Barrel Shotgun or The Slugger and also the weapons in bursts.

An energy weapon with the skill Energy Charge or a Melee weapon with the skill Special Attack can be extremely powerful if the charged attack is a critical hit.

The chance to cause a critical hit in combat is increased by

Initial Level: Each character starts with a 1% critical chance.


 * The Butcher skill (only Cain) increases the critical chance by 5% only for blades for each ranks until a total of 25%.
 * The Desert Soldier skill (only female character) increases the critical chance by 5% only for conventional weapons (weapon that uses 9mm) for each ranks until a total of 25%.
 * The Future Woman skill (only female character) increases the critical chance by 5% only for energy weapons for each ranks until a total of 25%.
 * The Heavy Hitter skill (only human male character) increases the critical chance by 5% only for Blunt weapon (Gloves, Clubs and Hammers) for each ranks until a total of 25%.
 * The Pyromaniac skill (only Cain) increases the critical chance by 5% when using a fire-based weapon (like the frag grenade, flamer, etc.) for each ranks until a total of 25%.
 * The Slayer skill increases the critical chance by 5% for each ranks until a total of 25%.
 * The Wastelander skill (only human male character) increases the critical chance by 10% only when using home-made weapons for each ranks until a total of 50%.

The type of weapon with a maximum critical chance with the skill required is the home-made weapons with a total of 75%.