Poison Damage

Targets turn green when poisoned, a state which stops unit damage regeneration and can apply poison damage to the target every frame of the state's length. While damage is displayed in points and length in seconds, both are calculated and applied using more precise units of measurement: damage is calculated and applied in bits, and length in frames. [1] Damage Length Points Bits Seconds Frames 1 256 1 25 Targets are poisoned if as little as 1 bit poison damage is applied per frame. Poison damage is displayed as the total damage applied over its length, but it's calculated by applying a bit rate (bit damage per frame) for a specified number of frames: a Toxic Small Charm applies 205 bit rate for 125 frames, which is displayed as 100 Poison Damage Over 5 Seconds (205*125/256 over 125/25). Poison damage from multiple attacks doesn't stack: if a target is already poisoned, then the rate and length of that poison will be overwritten by that of any subsequent attack which has an equal or greater rate. Rates are compared after all modifiers have been applied. [2] When players, hirelings or pets apply poison to a poisoned monster, their poison is applied for one frame instead of the current poison: if their poison has an equal or greater rate, it then overwrites the current poison and it gets applied for its length; if their poison has a lower rate, the current poison then continues for its remaining length. Rates are compared after all modifiers have been applied. More generally, poison damage does not get applied in frames in which any damage from other sources is applied (although poison and Open Wounds both apply simultaneously). [3] [4] When monsters apply poison to a player, hireling or pet, their poison is applied for one frame as well as the current poison: if their poison has an equal or greater rate, it then overwrites the current poison and it gets applied for its length; if their poison has a lower rate, the current poison then continues for its remaining length. Rabies and Poison Creeper can also apply additional frames of poison damage when applied to more than one monster. Poison damage can kill monsters, hirelings and pets but will only reduce players to 1 life (although poison damage from a subsequent attack would kill them if they remained on 1 hit life). [5]

Item

• If a single item has both a prefix and a suffix applying poison damage, then the rates and lengths of both are simply added. [6]

Source	Poison Damage			Bit Rate		Frames
	Min	Max	Seconds	Min	Max
Toxic Small Charm	100	100	5	205	205	125
Small Charm of Anthrax	50	50	6	86	86	150
Toxic Small Charm of Anthrax	313	313	11	291	291	275

• Displayed damage is rounded to the nearest point, although it should always be rounded down. When multiple items applying damage are equipped, then the rates are added and the lengths are averaged. [7]

Source	Poison Damage			Bit Rate		Frames
	Min	Max	Seconds	Min	Max
Toxic Small Charm of Anthrax	313	313	11	291	291	275
Blackbog's Sharp Cinquedeas	488	488	10	500	500	250
Perfect Emerald	100	100	7.16	143	143	179
Total				934	934	704

• 853 (934*234/256) poison damage over 9.36 ([704/3]/25) seconds is applied. Bits and frames are the smallest units of measurement, so calculations are rounded down to the nearest bit and frame. Gems, jewels and runes all count as separate items, even if they're socketed in a single item. [8]
• Length is calculated differently when multiple items applying poison damage are used with skills that apply a fraction of weapon damage. This applies to the following following skills:
  • Multiple Shot
  • Strafe
  • Blade Sentinel
  • Blade Fury
  • Blade Shield [9]
• Two items will apply poison damage over the sum of their lengths, while three or more items will just apply poison damage over the longest length of any of those items. [10]

Any socket

Template:D2 Poison |- !align=left|Rainbow Facet Jewel |37||37||2 |187||187||50 |49 |No |}

Template:D2 Poison affix |- !align=left|Jewel of Envy |20||20||2 |103||103||50 |1||1 |}

Helm

Template:D2 Poison |- !align=left|Wormskull Bone Helm |80||80||8 |102||102||200 |21 |No |}

Template:D2 Poison affix |- !align=left|Septic Circlet |6||6||2 |31||31||50 |1||1 |- !align=left|Circlet of Blight |7||7||3 |24||24||75 |3||5 |- !align=left|Circlet of Venom |21||21||4 |54||54||100 |11||15 |- !align=left|Circlet of Pestilence |50||50||5 |103||103||125 |18||25 |}

Amulet

Template:D2 Poison |- !align=left|Atma's Scarab Amulet |40||40||4 |102||102||100 |60 |No |}

Template:D2 Poison affix |- !align=left|Amulet of Blight |50||50||3 |171||171||75 |33||45 |}

Body armor

Template:D2 Poison |- !align=left|Dark Adherent Dusk Shroud |24||34||2 |125||175||50 |49 |No |}

Weapon

Template:D2 Poison |- |align=left|Chipped Emerald in weapon socket |10||10||3 |34||34||75 |1 |No |- |align=left|Flawed Emerald in weapon socket |20||20||4 |51||51||100 |5 |No |- |align=left|Emerald in weapon socket |40||40||5 |82||82||125 |12 |No |- |align=left|Flawless Emerald in weapon socket |60||60||6.08 |101||101||152 |15 |No |- |align=left|Perfect Emerald in weapon socket |100||100||7.16 |143||143||179 |18||No |- |align=left|Tal Rune in weapon socket |75||75||5 |154||154||125 |17||No |- |align=left rowspan=2|Venom weapon |273||273||6 |466||466||150 |49||No |}

Template:D2 Poison affix |- !align=left|Septic Weapon |6||6||2 |31||31||50 |1||1 |- !align=left|Foul Weapon |12||12||3 |41||41||75 |7||10 |- !align=left|Corrosive Weapon |80||80||4 |205||205||100 |15||20 |- !align=left|Toxic Weapon |150||150||5 |308||308||125 |26||35 |- !align=left|Pestilent Weapon |275||275||6 |470||470||150 |37||50 |- !align=left|Weapon of Blight ¹ |2||2||2 |8||8||50 |1||1 |- !align=left|Weapon of Blight ² |7||7||3 |24||24||75 |3||5 |- !align=left|Weapon of Venom ² |21||21||4 |54||54||100 |11||15 |- !align=left|Weapon of Pestilence ² |50||50||5 |103||103||125 |18||25 |- !align=left|Weapon of Anthrax ² |100||100||6 |171||171||150 |25||33 |}

¹ Excluding scepters, staves and orbs; can only spawn if alvl <5
² Excluding rods (scepters, staves and wands) and orbs

Missile weapon

Template:D2 Poison |- !align=left|Ichorsting Crossbow |30||30||3 |102||102||75 |18 |No |- |align=left|Edge missile weapon |75||75||5 |154||154||125 |25 !Yes |- !align=left|Pus Spitter Siege Crossbow |150||150||8 |192||192||200 |36 |No |}

Axe

Template:D2 Poison |- !align=left|Rakescar War Axe |38||38||3 |128||128||75 |27||No |- !align=left|Guardian Naga Naga |250||250||10 |256||256||250 |48||No |}

Dagger

Template:D2 Poison |- !align=left|The Jade Tan Do Kris |180||180||4 |460||460||100 |19||No |- !align=left|Blackbog's Sharp Cinquedeas |488||488||10 |500||500||250 |38||No |}

Hammer

Template:D2 Poison |- |align=left|Immortal King's Stone Crusher Ogre Maul (5 items) |204||204||6 |349||349||150 |76 |No |}

Javelin

Template:D2 Poison |- !align=left|Gargoyle's Bite Winged Harpoon |293||293||10 |300||300||250 |70 |No |}

Polearm

Template:D2 Poison |- |align=left|Insight polearm |75||75||5 |154||154||125 |27 !Yes |}

Scepter

Template:D2 Poison |- |align=left|Holy Thunder scepter |75||75||5 |154||154||125 |21||No |- !align=left|The Fetid Sprinkler Holy Water Sprinkler |160||160||4 |409||409||100 |38||No |}

Spear

Template:D2 Poison |- !align=left|Viperfork Mancatcher |325||325||10 |333||333||250 |71||No |- !align=left|Arioc's Needle Hyperion Spear |394||394||10 |403||403||250 |81||No |}

Staff

Template:D2 Poison |- !align=left|Serpent Lord Long Staff |12||12||3 |40||40||75 |9||No |- |align=left|Insight staff |75||75||5 |154||154||125 |27 !Yes |}

Sword

Template:D2 Poison |- !align=left|Hellplague Long Sword |28||56||6 |48||96||150 |22||No |- |align=left|Spirit sword |75||75||5 |154||154||125 |25 !Yes |- !align=left|Blacktongue Bastard Sword |113||113||6 |192||192||150 |26||No |- !align=left|Bul-Kathos' Tribal Guardian Mythical Sword |50||50||2 |255||255||50 |66||No |- !align=left|Plague Bearer Rune Sword |300||300||8 |384||384||200 |41||No |- !align=left|The Vile Husk Tusk Sword |250||250||6 |426||426||150 |44||No |}

Shield

Template:D2 Poison |- !align=left|Radament's Sphere Ancient Shield |80||80||4 |204||204||100 |50||No |}

Shrunken head

Template:D2 Poison affix |- !align=left|Shrunken head |2||7||3 |8||24||75 | -||1 |- !align=left|Shrunken head |5||14||3 |16||48||75 | -||15 |- !align=left|Shrunken head |13||28||4 |32||72||100 | -||25 |- !align=left|Shrunken head |25||50||4 |64||128||100 | -||33 |}

• One of the above always spawns on any shrunken head which isn't Unique or Set quality.

Ring

Template:D2 Poison affix |- !align=left|Ring of Blight |50||50||3 |171||171||75 |33||45 |}

Belt

Template:D2 Poison |- !align=left|Snakecord Light Belt |12||12||3 |40||40||75 |12||No |}

Gloves

Template:D2 Poison |- !align=left|Sander's Taboo Heavy Gloves |9||11||3 |30||36||75 |28||No |- !align=left|Venom Grip Demonhide Gloves |60||60||4 |153||153||100 |29||No |}

Charm

Grand Charm

Template:D2 Poison affix |- !align=left|Septic Grand Charm |5||5||3 |18||18||75 |1||1 |- !align=left|Foul Grand Charm |15||15||4 |39||39||100 |9||12 |- !align=left|Toxic Grand Charm |50||50||5 |103||103||125 |20||27 |- !align=left|Pestilent Grand Charm |100||100||6 |171||171||150 |34||42 |- !align=left|Grand Charm of Blight |6||6||3 |21||21||75 |1||1 |- !align=left|Grand Charm of Venom |15||15||4 |39||39||100 |4||6 |- !align=left|Grand Charm of Pestilence |25||25||5 |52||52||125 |10||14 |- !align=left|Grand Charm of Anthrax |50||50||6 |86||86||150 |15||21 |}

Large Charm

Template:D2 Poison affix |- !align=left|Septic Large Charm |10||10||3 |35||35||75 |6||9 |- !align=left|Foul Large Charm |30||30||4 |77||77||100 |19||26 |- !align=left|Toxic Large Charm |90||90||5 |185||185||125 |38||46 |- !align=left|Pestilent Large Charm |175||175||6 |299||299||150 |58||66 |- !align=left|Large Charm of Blight |6||6||3 |21||21||75 |3||5 |- !align=left|Large Charm of Venom |15||15||4 |39||39||100 |9||13 |- !align=left|Large Charm of Pestilence |25||25||5 |52||52||125 |17||23 |- !align=left|Large Charm of Anthrax |50||50||6 |86||86||150 |25||33 |}

Small Charm

Template:D2 Poison affix |- !align=left|Septic Small Charm |15||15||3 |52||52||75 |13||18 |- !align=left|Foul Small Charm |50||50||4 |128||128||100 |31||39 |- !align=left|Toxic Small Charm |100||100||5 |205||205||125 |55||63 |- !align=left|Pestilent Small Charm |175||175||6 |299||299||150 |80||88 |- !align=left|Small Charm of Blight |6||6||3 |21||21||75 |6||9 |- !align=left|Small Charm of Venom |15||15||4 |39||39||100 |15||20 |- !align=left|Small Charm of Pestilence |25||25||5 |52||52||125 |24||32 |- !align=left|Small Charm of Anthrax |50||50||6 |86||86||150 |36||44 |}

Set bonus

Template:D2 Poison |- |align=left|Berserker's Arsenal (Full) |5||9||3 |16||32||75 |3||No |- |align=left|Infernal Tools (2 items) |8||8||3 |25||25||80 |5||No |- |align=left|The Disciple (3 items) |22||22||3 |75||75||75 |49||No |}

Missile

• Raise Skeletal Mage summons Necromages which fire missiles with lvl = if(slvl<4,0,[(slvl-2)/2])+Skeleton Mastery.lvl).

Missile	Bit Rate at Level					Frames
	1-8	9-16	17-22	23-28	>28
Necromage1	lvl+5	(2*lvl)-3	(4*lvl)-35	(6*lvl)-79	(8*lvl)-135	250+(250*lvl)

Skill

• Skill level is set when the player uses the skill: adding or removing skill bonuses won't have any effect on rate or length if there's a delay between using the skill and applying the poison.

Skill		Bit Rate at Level					+% Poison Damage	Frames
		1-8	9-16	17-22	23-28	>28
Poison Javelin	Min	(16*slvl)+16	(32*slvl)-112	(48*slvl)-368	(64*slvl)-720	(96*slvl)-1616	12*Plague Javelin.blvl	150+(50*slvl)
	Max	(16*slvl)+32	(36*slvl)-128	(52*slvl)-384	(68*slvl)-736	(84*slvl)-1184
Plague Javelin	Min	(48*slvl)+32	(96*slvl)-352	(160*slvl)-1376	(320*slvl)-4896	(480*slvl)-9376	10*Poison Javelin.blvl	65+(10*slvl)
	Max	(48*slvl)+80	(96*slvl)-304	(160*slvl)-1328	(320*slvl)-4848	(480*slvl)-9328
Venom	Min	(384*slvl)+1152	(512*slvl)+128	(640*slvl)-1920	(768*slvl)-4736	(896*slvl)-8320		10
	Max	(384*slvl)+1664	(512*slvl)+640	(640*slvl)-1408	(768*slvl)-4224	(896*slvl)-7808
Poison Creeper	Min	(7*slvl)+5	(12*slvl)-35	(15*slvl)-83	(17*slvl)-127	(19*slvl)-183		100
	Max	(7*slvl)+9	(12*slvl)-31	(15*slvl)-79	(17*slvl)-123	(19*slvl)-179
Rabies	Min	(32*slvl)+16	(40*slvl)-48	(56*slvl)-304	(88*slvl)-1008	(128*slvl)-2128	18*Poison Creeper.blvl	90+(10*slvl)
	Max	(32*slvl)+80	(40*slvl)+16	(56*slvl)-240	(88*slvl)-944	(128*slvl)-2064
Poison Dagger	Min	(20*slvl)+16	(30*slvl)-64	(40*slvl)-224	(46*slvl)-356	(52*slvl)-524	20*(PE.blvl+PN.blvl)	40+(10*slvl)
	Max	(20*slvl)+60	(30*slvl)-20	(40*slvl)-180	(46*slvl)-312	(52*slvl)-480
Poison Explosion	Min	(32*slvl)+96	(64*slvl)-160	(96*slvl)-672	(128*slvl)-1376	(160*slvl)-2272	15*(PD.blvl+PN.blvl)	40+(10*slvl)
	Max	(32*slvl)+352	(64*slvl)+96	(96*slvl)-416	(128*slvl)-1120	(160*slvl)-2016
Poison Nova	Min	(64*slvl)+192	(96*slvl)-64	(144*slvl)-832	(224*slvl)-2592	(256*slvl)-3488	10*(PD.blvl+PE.blvl)	50
	Max	(64*slvl)+400	(96*slvl)+144	(144*slvl)-624	(224*slvl)-2384	(256*slvl)-3280

• Level >36 Poison Javelin displays higher minimum than maximum damage because the minimum bit rate added per level for level >28 is higher than the maximum bit rate added. When this occurs, the minimum damage becomes the maximum and the maximum damage becomes the minimum. [11]
• Level 30 Poison Dagger with 20 skill points each in Poison Explosion and Poison Nova applying a +800% (20*(20+20)) poison damage synergy bonus applies the following:

Min bit rate = ((52*30)-524)*(100+800)/100 = (1560-524)*900/100 = 1036*9 = 9324 Min poison = 9324*340/256 = 12,383

Max bit rate = ((52*30)-480)*(100+800)/100 = (1560-480)*900/100 = 1080*9 = 9720 Max poison = 9720*340/256 = 12,909

Frames = 40+(10*30) = 40+300 = 340 0 Seconds = 340/25 = 13.6

Skill and items

• While most skills are treated as separate sources of poison damage whose rates (and accompanying lengths) compete with those of other skills and items, Poison Dagger and the javelins (but not the clouds) of Poison and Plague Javelins combine the skill's rate with any item rates. Length is calculated by summing skill and item lengths and dividing by the number of items. [12]

Source	Poison Damage			Bit Rate		Frames
	Min	Max	Seconds	Min	Max
Toxic Small Charm of Anthrax	313	313	11	291	291	275
Blackbog's Sharp Cinquedeas	488	488	10	500	500	250
Perfect Emerald	100	100	7.16	143	143	179
Level 30 Poison Dagger	12,383	12,909	13.6	9324	9720	340
Total				10258	10654	1044

Min poison = 10258*348/256 = 13,944

Max poison = 10654*348/256 = 14,482

Seconds = [1,044/3]/25 = 13.92

• If the only item used were Blackbog's Sharp Cinquedeas, 9824-10220 bit rate for 590 ((250+340)/1) frames would apply 22,641-23,553 poison damage over 23.6 (590/25) seconds. Although the rate is lower with only one item, the length can be significantly longer and results in far more damage from a single stab.

Venom

• Venom's rate is applied to any weapon's attack made between its casting and expiration, and adds to any rate applied by items. However, its 10 frame length overrides those of any items.

Source	Poison Damage			Bit Rate		Frames
	Min	Max	Seconds	Min	Max
Toxic Small Charm of Anthrax	313	313	11	291	291	275
Blackbog's Sharp Cinquedeas	488	488	10	500	500	250
Perfect Emerald	100	100	7	143	143	179
Level 15 Venom	305	325	0.4	7808	8320	10
Total				8742	9254	10

Min poison = 8742*10/256 = 341

Max poison = 9254*10/256 = 361

Seconds = 10/25 = 0.4

• Venom's length does not override those of the skills Poison Dagger and Poison and Plague Javelins. Casting Venom can thus significantly increase the rate applied by these skills while not reducing length. Since Venom effectively creates a single source which sums the rates of Venom and items but which only applies for Venom's length, the length is the sum of the skill length and that of Venom. [13]

Source	Poison Damage			Bit Rate		Frames
	Min	Max	Seconds	Min	Max
Toxic Small Charm of Anthrax	313	313	11	291	291	275
Blackbog's Sharp Cinquedeas	488	488	10	500	500	250
Perfect Emerald	100	100	7	143	143	179
Level 30 Poison Dagger	12,383	12,909	13.6	9324	9720	340
Level 15 Venom	305	325	0.4	7808	8320	10
Total				18066	18974	350

Min poison = 18066*350/256 = 24,699

Max poison = 18974*350/256 = 25,941

Seconds = 350/25 = 14

+% Poison Skill Damage

• Certain items apply a percentage increase to the rate which is applied after any +% poison damage synergy bonus to skill damage, and melee attack poison damage. Character screen displays +% PSD being applied to ranged attack poison damage as well, but this is not actually the case.
• When using two weapons +% PSD of both is applied to skill damage, or attack damage of either weapon when using a melee attack.
• Applies to damage when applied and missiles when created: if there is a delay between skill usage and damage or missile creation (as there can be with Poison and Plague Javelin clouds, and Rabies contagion missiles), switching weapons or other equipment to apply more +% PSD may result in more damage.
• Does not apply to pets summoned by the user, so it does not apply to Poison Creeper or Necromage missiles. [14]
• Applies to Venom attack damage before it is added, then again when using a melee attack.
• Equipping Trang-Oul's Claws Heavy Bracers applies +25% PSD to level 15 Venom when cast:

Min bit rate = 7808*(100+25)/100 = 7808*1.25 = 9760

Max bit rate = 8320*(100+25)/100 = 8320*1.25 = 10400

Source	Poison Damage			Bit Rate		Frames
	Min	Max	Seconds	Min	Max
Toxic Small Charm of Anthrax	313	313	11	291	291	275
Blackbog's Sharp Cinquedeas	488	488	10	500	500	250
Perfect Emerald	100	100	7.16	143	143	179
Level 15 Venom	305	325	0.4	9760	10400	10
Total				10694	11334	10
Level 30 Poison Dagger	12,383	12,909	13.6	9324	9720	340

• +25% PSD is now applied, resulting in the following poison damage over 14 ((340+10)/25) seconds:

Min bit rate = (10694*(100+25)/100)+(9324*(100+25)/100) = (10694*1.25)+(9324*1.25) = 13367+11655 = 25022 Min poison = 25022*350/256 = 34,209

Max bit rate = (11334*(100+25)/100)+(9720*(100+25)/100) = (11334*1.25)+(9720*1.25) = 14167+12150 = 26317 Max poison = 26317*350/256 = 35,980

Lower Resist

• Target's Poison Resist % reduces poison's rate, and PR >99% makes a monster Immune to Poison. Players and hirelings normally have a PR 75% ceiling, although this can be increased to PR 95% by applying +% Maximum Poison Resist.
• Lower Resist applies PR -%, although it's applied at 1/5 effectiveness against Immune to Poison monsters: level 10 LR's PR -55% is reduced to PR -11% [55/5]. PR -100% is the floor.
• 25,022-26,317 bit rate for 350 frames results in 34,209-35,980 poison damage being applied over 14 seconds to a PR 0% target. Casting level 10 LR (PR -55%) results in the following:

Min bit rate = 25022*(100-(0-55))/100 = 25022*(100+55)/100 = 25022*1.55 = 38784 Min poison = 38784*350/256 = 53,025

Max bit rate = 26317*(100-(0-55))/100 = 26317*(100+55)/100 = 26317*1.55 = 40791 Max poison = 40791*350/256 = 55,768

Frames = 350 0 0 0 Seconds = 350/25 = 14

• LR is applied when the target is poisoned, so it can be overwritten by another curse immediately afterwards: even if LR is required to break immunity, once poison has been applied its rate and length remain unchanged, even if the monster becomes Immune to Poison again. [15]

-% Enemy Poison Resistance

• Reduces a target's PR % like LR, but only if PR < 100% i.e. not Immune to Poison. However, unlike LR -% EPR also applies to length, effectively applying Poison Length Reduced by -%. [16]
• Monsters have no PLR % so -% EPR increases poison length by the displayed amount: PLR -100% is the floor. The only exceptions are the Ancients, whose equipment can spawn with PLR % suffixes: Korlic and Talic can spawn with PLR >99%, which always reduces poison length to a single frame. [17]
• Players and hirelings have a PLR 75% ceiling, although the same difficulty level penalties that apply to Resist % apply (-40% in Nightmare and -100% in Hell). [18]
• Like LR, -% EPR is applied when the target is poisoned. Once poison has been applied its rate and length remain unchanged, so -% EPR can be removed afterwards without affecting damage or length. [19]
• 25,022-26,317 bit rate for 350 frames results in 34,209-35,980 poison damage being applied over 14 seconds to a PR 0% target. Casting level 10 LR (PR -55%) and equipping Trang-Oul's Wing Cantor Trophy with two other items from the set to apply its -25% EPR partial set bonus results in the following:

Min bit rate = 25022*(100-(0-55-25))/100 = 25022*(100+80)/100 = 25022*1.8 = 45039 Min poison = 45039*437/256 = 76,882

Max bit rate = 26317*(100-(0-55-25))/100 = 26317*(100+80)/100 = 26317*1.8 = 47370 Max poison = 47370*437/256 = 80,862

Frames = 350*(100-(0-25))/100 = 350*(100+25)/100 = 350*1.25 = 437 Seconds = 437/25 = 17.48

Calculation

Download

• Poison damage calculator.xls (onderduiker) Updated 24 March 2010

Online

• D2.de Skill Calc (inDiablo.de) Skills only
• Gift Kalkulator (D2Chars.de) Poison Dagger, Poison Explosion and Poison Nova with items, +% PSD, LR, -% EPR and PR %
• Skill Calculator (Dieter Gottwald) Poison Dagger, Poison Explosion and Poison Nova with +% PSD and PR %
• Kalkulatoren: Gift-Schaden (D2Wissen.de) Items with Venom, Poison Dagger, Poison Javelin or Plague Javelin and +% PSD

Below is a summary of all the steps in the calculation of poison damage outlined in the preceding sections. To express total damage in points applied over a length in seconds:

Points	= [ Rate * Frames / 256 ]	Seconds	= Frames / 25
0
Rate	= [ ( [ [B * S] * M ] + [ ( I + [V * M] ) * M ] ) * R ]	Frames	= [F * R]
0
[ ] Round down B Skill rate I Item rates V Venom rate M +X% Poison Skill Damage M = (100+X)/100 S +X% poison damage synergy S = (100+X)/100 R Resist R = (100-X)/100 If P >= 100 and P-[L/5] < 100 then X = P-[L/5] else R = 0 If P < 100 then X = max(P-(L+E),-100) P Poison Resist X% P = X L Lower Resist (PR -X%) L = X E -X% EPR E = X		F Items = item lengths/items Items + Skill = (skill length + item lengths)/items Items + Venom = Venom length Skill + Venom = skill length + Venom length R Resist R = (100-X)/100 If P < 100 then X = max(P-E,-100) else F = 1 P Poison Length Reduced by X% P = X E -X% Enemy Poison Resistance E = X

• Ideally damage is calculated measuring rate in bits and length in frames. It's also possible to calculate damage measuring rate in poison damage/second and length in seconds, which can be derived directly from displayed damage. However, the result will only be an approximation and rounding down should only be done at the end of the calculation for maximum accuracy.
• If a single item has both a prefix and a suffix applying poison damage, then the rates and lengths of both are simply added.
• Gems, jewels and runes all count as separate items, even if they're socketed in a single item.
• Item and Venom rate are only added to the skill rates of Poison Dagger and the javelins (but not the clouds) of Poison Javelin and Plague Javelin.
• +% PSD isn't applied to item and Venom rate when applied by ranged attacks.
• Length is calculated differently when multiple items applying poison damage are used with skills that apply a fraction of weapon damage. Two items will apply poison damage over the sum of their lengths, while three or more items will just apply poison damage over the longest length of any of those items.

References

• Open Wounds (Technical Discussion)
• Schadensunterbrechung: Giftnova und anderer Schaden (inDiablo.de)
• Wiki Progress (Technical Discussion)
• Bkelly, The Tao of Poison (web.archive.org)
• Librarian, poison damage (FAQtoids)
• Meej, Clarifications on 1.10 Poison needed (Technical Discussion)
• Onderduiker, ANY damage stops unit damage regeneration (Technical Discussion)
• Onderduiker, Monster Resistances and Immunities Guide (Technical Discussion)
• Onderduiker, Poison and Plague Javelins (Javazon Room)
• Othin, Poison Basics (D2library)