Critical Hit Rate

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Revision as of 22:17, 13 February 2013 by Slycer (talk | contribs) (→‎Merit Points)

For melee weapons, critical hit rate is the sum of the base rate (5%), gear/atma (0-100%), merit points (0-5%), Buffs, Weapon Skill modifiers, and player Dexterity relative to target Agility (also known as dDEX, 0-15%). As there is no cap to critical hit rate, it can be taken all the way to 100%, guaranteeing that every attack is a critical hit. Category-specific caps are marked. It also only takes whole number values, so it is impossible to have something like a 12.5% Critical Hit Rate.

Weapon Skills with the description "Chance of Critical Hit varies with TP" modify Critical Hit Rate during Weapon Skill. Generally, the base modification at 100TP varies from 0% to 40%, and extra Critical Hit Rate is awarded for TP over 100.

Example: A Thief has 115 Dexterity, Level 5 Critical Hit Rate Merits, +4% Critical Hit Rate in gear, and is fighting a monster with 96 Agility. They have a 5% + 4% + 5% + 0% + 2% (dDEX=19) = 16% Critical Hit Rate.

For ranged weapons, critical hit rate is the sum of the base rate (5%), gear/atma (0-100%), merit points (0-5%), Buffs, Weapon Skill modifiers, and player Agility relative to target Agility (also known as dAGI, no known cap). Dexterity does not affect critical hit rate for ranged weapons.



Melee Critical Hit Rate (dDEX)

dDEX (Player DEX - Target AGI) determines the contribution of Dexterity to melee critical hit rate. This is added on to the base rate and merits to determine the total critical hit rate. Because this value depends on the target's Agility, which will be determined by its level and job combination, Critical Hit builds are sensible in some places and not sensible in others.

Based on the chart below, you can see that there is an extremely significant jump in critical hit rate when dDEX is increased from 40 to 50 (from 4% at dDEX=39 to 15% at dDEX=50), but no further boost to critical hit rate once dDEX is greater than 50.

dDEX Crit Rate
 0-6  +0%
 7-13  +1%
 14-19  +2%
 20-29  +3%
 30-39  +4%
 40-50  +(dDEX-35)%

Ranged Critical Hit Rate (dAGI)

dAGI (Player AGI - Target AGI) determines the contribution of Agility to ranged critical hit rate. This is added on to the base rate and merits to determine the total critical hit rate. This value does depend on the target's Agility, but there are few times when critical hit rate builds are optimal (vs. times when they're less optimal) because adding the same amount of AGI always grants the same amount of critical hit rate and ranged critical hits are a constant multiplier of the damage you would have done otherwise.

Crit Rate = +floor( dAGI÷10 )%

This has been tested for the range dAGI = 0~90.

Merit Points

Critical hit rate is also a merit category available to all jobs. It can be merited a total of 5 times. Each merit upgrade grants a 1% increase in critical hit rate. It costs 15 merits to fully upgrade (1>2>3>4>5). This is likely the most popular merit choice in the "other" category.

Testing Critical Hit Rate

If you have something giving you an unknown amount of Critical Hit Rate, then the easiest way to find it is to use Abyssea Atmas and gear with known potency to force a 100% Critical Hit Rate. Lets say you have Y% known critical hit rate and X% from an unknown source. If you swing your weapon (or use your Weapon Skill) and get a non-crit return, you know that:

100% > Y% + X%

Furthermore, if you manage to Critical Hit 303 times in a row, you can say with 95% certainty that your Critical Hit Rate is 100%. You can think of it like this:

.99^n = Probability of Critical Hitting "n" times in a row if your critical hit rate is actually 99%.

Now, there's also a chance that you critical hit "n" times in a row with a 98% critical hit rate, so to accurately calculate the odds you have to add up all the .XX^n values over the range of possibilities. If you're using something like Razed Ruins and Gnarled Horn with 5 Critical Hit Rate merits, you know that your minimum Critical Hit rate is 75%. Then the equation would become:

.99^n + .98^n + .97^n ... .75^n = Probability of Critical Hitting "n" times in a row if your Critical Hit rate is actually between 99% and 75%.

That equation happens to equal 95% when n = 303, hence the above statement.

Example: So say that you have a piece of equipment (like Assassin's Vest) with an unknown boost to Critical Hit Rate. The testing method would recommend you go to Abyssea, put on Atma of the Gnarled Horn, Atma of the Razed Ruins, and Atma of the Dark Depths (95% Critical Hit Rate with 5 merits) and the equipment. Swing away at something, and increase your critical hit rate by 1% per non-crit. The first sign of negative evidence (a non-crit) is enough to increment. At the final level, you should end up Critical Hiting 303 times in a row without seeing any regular hits, which makes you 95% confident that you've found your target value. From that point, you would add up your sources of critical hit rate and subtract them from 100%. The remainder is the critical hit rate on the equipment.

Past Critical Hit Rate tests relied on long parses against Hpmedes (N=10000+, as is seen in the references), Abyssea brought with it the possibility of a new way to test unknown Critical Hit Rate boosts. Overall, this is much faster than a similarly accurate Hpemde parse. On average, you would expect to swing 531 times to determine the critical hit rate of an unknown source with 95% confidence. The test will go much faster if you undershoot Critical Hit rate with your initial guess than if you overshoot it, and you should be able to get within 5% very quickly. This same method can be applied to Weapon Skills, using them as the X% unknown Critical Hit Rate.

Enhanced By

Abilities

  • Rogue's Roll: Up to ~+20% critical hit rate depending on result.
  • Blood Rage: +20% critical hit rate while in effect.
  • Impetus: Up to +50% critical hit rate with consecutively landed attacks.
  • Mighty Strikes: 100% critical hit rate while in effect.

Equipment

Item Level Slot Jobs Crit. Hit Rate
Jupiter's Staff 51 Weapon All Jobs 15%
Thunder Staff 51 Weapon All Jobs 15%
Cruadin 69 Weapon PLD DRK 15% (Campaign)
Dies Irae 99 Weapon WAR 10%
Skadi's Armor Set +1 99 Set THF BST RNG COR DNC 9% (max)
Primate Staff +1 73 Weapon MNK WHM PLD DRG 7%
Barkborer 72 Weapon BST 7% (vs. Plantoid)
Ermine's Tail 72 Weapon WAR THF PLD DRK BRD RNG SAM NIN DRG COR PUP DNC 7% (vs. Lizards)
Eventreuse 72 Weapon WAR 7% (vs. Plantoid)
Koggelmander 72 Weapon WAR RDM THF PLD DRK BST BRD RNG NIN DRG BLU COR 7% (vs. Vermin)
Onishibari 72 Weapon NIN 7% (vs. Beasts)
Scheherazade 72 Weapon DRK 7% (vs. Lizards)
Zaide 72 Weapon DRG 7% (vs. Beasts)
Zonure 72 Weapon WAR WHM PLD 7% (vs. Vermin)
Kamewari 70 Weapon SAM 7% (vs. Arcana)
Anubis's Knife 65 Weapon WAR THF DRK RNG NIN COR PUP DNC 7% (Poison)
Athos's Armor Set 96~99 Set MNK THF RNG NIN BLU COR PUP DNC 3~6% (Set)
Smn. Doublet +2 90 Body SMN 6% (Avatar)
Destroyers 73 Weapon WAR MNK RDM THF PLD DRK BST RNG DNC 6% (Latent)
Gravedigger 73 Weapon WAR BLM DRK BST 6% (Latent)
Heart Snatcher 73 Weapon WAR THF PLD DRK BRD RNG SAM NIN DRG COR PUP DNC 6% (Latent)
Thyrsusstab 73 Weapon WAR MNK WHM BLM PLD BRD DRG SMN SCH 6% (Latent)
Dissector 72 Weapon WAR RDM THF PLD DRK BRD RNG NIN DRG BLU 6% (Latent)
Gondo-Shizunori 72 Weapon WAR SAM DRG 6% (Latent)
Michishiba 72 Weapon SAM NIN 6% (Latent)
Morgenstern 72 Weapon WHM PLD 6% (Latent)
Rampager 72 Weapon WAR DRK 6% (Latent)
Retributor 72 Weapon WAR DRK BST RNG 6% (Latent)
Senjuinrikio 72 Weapon NIN 6% (Latent)
Subduer 72 Weapon WAR PLD DRK 6% (Latent)
Kumarbi's Akar 99 Body WAR PLD DRK BST SAM DRG 5%
Mustela Harness Set 96 Set MNK THF RNG SAM NIN COR PUP DNC 5% (Set)
Coruscanti 95 Weapon THF BRD COR DNC 5%
Iga Ningi +2 89 Body NIN 5%
Jing. Greatsword 87 Weapon WAR DRK 5%
Nvrch. Gants +2 87 Hands COR 5%
Hachiryu Haramaki 75 Body WAR MNK RNG SAM NIN 5%
Kawahori Kabuto 75 Head MNK SAM NIN 5% (Blind)
Skadi's Armor Set 75 Set THF BST RNG COR 5% (Set)
Rai Kunimitsu 74 Weapon NIN 5%
Kinkobo 73 Weapon MNK WHM PLD DRG 5%
Primate Staff 73 Weapon MNK WHM PLD DRG 5%
Asn. Jambiya 70 Weapon WAR THF PLD DRK BRD RNG SAM NIN DRG COR PUP DNC 5% (Assault)
Kumokirimaru 70 Weapon SAM 5%
8% (vs. Vermin)
Onikiri 65 Weapon SAM 5% (vs. Demons)
Kitsutsuki 64 Weapon NIN 5% (vs. Plantoids)
Arcanabane 59 Weapon WAR DRK BST RNG 5% (vs. Arcana)
Kidney Dagger 56 Weapon WAR BLM RDM THF PLD DRK BST BRD RNG SAM NIN DRG SMN SCH 5%
Asteria 99 Weapon THF BRD DNC 4%
Thaumas Hat 99 Head MNK THF RNG NIN BLU COR PUP DNC 4%
Usukane Haramaki +1 99 Body MNK SAM NIN PUP 4%
Laceratrice 95 Weapon WAR 4%
Lux Pugio 95 Weapon THF BRD COR DNC 4%
Bale Cuirass +2 89 Body DRK 4%
Oneiros Lance 88 Weapon DRG 4%
Nvrch. Gants +1 87 Hands COR 4%
Raid. Culottes +2 83 Legs THF 4%
Juogi +1 80 Body MNK SAM NIN PUP 4%
Smn. Doublet +1 75 Body SMN 4% (Avatar)
Hecatomb Subligar +1 73 Legs WAR THF PLD DRK BST BRD DRG Augment-Icon.png 1~4%
Euxine Hat +3 99 Head MNK THF RNG NIN BLU COR PUP DNC 3%
Nefarious Collar 99 Neck All Jobs 3%
Wurrukatte Boots 99 Feet MNK THF RNG NIN BLU COR DNC 3%
Kacura Harness +1 96 Body MNK THF RNG NIN BLU COR DNC 3%
Asn. Vest +2 90 Body THF 3%
Mextli Harness 90 Body MNK THF BST RNG NIN BLU COR PUP DNC 3% (Sphere)
Iga Ningi +1 89 Body NIN 3%
Frn. Manoplas +2 87 Hands BST 3%
Ravager's Mask +2 85 Head WAR 3%
Iga Dochugappa 84 Back NIN 3%
Sylvan Bragues +2 83 Legs RNG 3%
Ferus Algol 80 Weapon WAR DRK 3%
Juogi 80 Body MNK SAM NIN PUP 3%
Afflictors 77 Weapon WAR MNK BST NIN PUP 3%
Leonine Mask 75 Head WAR MNK THF BST NIN DNC 3%
Organics 75 Weapon WAR PLD DRK 3%
Summoner's Dblt. 74 Body SMN 3% (Avatar)
Pygme Sainti 73 Weapon PUP 3%
Cletine 72 Weapon DRG 3%
Zahak's Mail 71 Body WAR PLD DRK BST DRG 3%
Fudo 70 Weapon NIN 3%
Tonbo-Giri 68 Weapon SAM DRG 3% (vs. Vermin)
Claymore Grip 65 Grip All Jobs 3%
Nuevo Coselete 75 Body WAR PLD DRK SAM DRG Augment-Icon.png 3%
Mirke Wardecors 75 Body MNK THF BST RNG NIN BLU COR PUP DNC Augment-Icon.png 3%
Royal Redingote 75 Body WHM BLM RDM BRD SMN SCH Augment-Icon.png 3%
Champion's Galea 75 Head WAR PLD DRK SAM DRG Augment-Icon.png 3% (Pet)
Anwig Salade 75 Head MNK THF BST RNG NIN BLU COR PUP DNC Augment-Icon.png 3% (Pet)
Selenian Cap 75 Head WHM BLM RDM BRD SMN SCH Augment-Icon.png 3% (Pet)
Seiryu's Kote 75 Hands WAR MNK BST BRD RNG SAM NIN Augment-Icon.png 1~3%
Valkyrie's Sabatons 75 Feet WAR PLD DRK Augment-Icon.png 1~3%
Hecatomb Subligar 73 Legs WAR THF PLD DRK BST BRD DRG Augment-Icon.png 1~3%
Shura Togi +1 73 Body MNK SAM NIN Augment-Icon.png 1~3%
Grandoyne's Mail 99 Body WAR PLD DRK BST SAM DRG 2%
Euxine Hat +2 99 Head MNK THF RNG NIN BLU COR PUP DNC 2%
Kacura Leggings +1 96 Feet MNK THF RNG NIN BLU COR DNC 2%
Kacura Mittens +1 96 Hands MNK THF RNG NIN BLU COR DNC 2%
Calmecac Subligar 89 Legs WAR PLD DRK BST SAM DRG 2%
Frn. Manoplas +1 87 Hands BST 2%
Nemus Peti 87 Body WAR RDM THF PLD DRK BST BRD RNG SAM NIN DRG BLU COR DNC 2%
Nemus Peti +1 87 Body WAR RDM THF PLD DRK BST BRD RNG SAM NIN DRG BLU COR DNC 2%
Sylvan Bragues +1 83 Legs RNG 2%
Perle Hauberk 78 Body WAR PLD DRK BST SAM DRG 2%
Ebon Vest 71 Body THF NIN DNC 2%
Ebur Vest 71 Body THF NIN DNC 2%
Furia Vest 71 Body THF NIN DNC 2%
Nuevo Coselete 75 Body WAR PLD DRK SAM DRG Augment-Icon.png 2% (Pet)
Mirke Wardecors 75 Body MNK THF BST RNG NIN BLU COR PUP DNC Augment-Icon.png 2% (Pet)
Royal Redingote 75 Body WHM BLM RDM BRD SMN SCH Augment-Icon.png 2% (Pet)
Kirin's Osode 75 Body WAR MNK BST BRD RNG SAM NIN Augment-Icon.png 1~2%
Shadow Sabatons 75 Feet WAR PLD DRK Augment-Icon.png 1~2%
Byakko's Axe 74 Weapon WAR DRK Augment-Icon.png 1~2%
Shura Togi 73 Body MNK SAM NIN Augment-Icon.png 1~2%
Kacura Subligar +1 96 Legs MNK THF RNG NIN BLU COR DNC 1%
Ebon Tights 71 Legs THF NIN DNC 1%
Ebur Tights 71 Legs THF NIN DNC 1%
Furia Tights 71 Legs THF NIN DNC 1%
Dilaram's Sollerets 95 Feet WAR PLD DRK BST SAM NIN -8%

See Also