Calculating Magic Damage


Actual Damage[edit]

Actual Damage is calculated by multiplying the following factors in order and flooring after each step.
1) D
2) Multiple-Target Damage Reduction
3) resist
4) Staff Bonus
5) Day | Weather Bonus
6) Magic Burst Bonus
6a) Magic Burst Bonus Gear #1
6b) Magic Burst Bonus Gear #2
7) MAB / MDB
8) Target Magic Damage Adjustment

There is reason to believe that the magic burst portion is calculated prior to MAB. Further testing would be necessary to confirm the order of the other parts with respect to magic bursts.

Explanation of Factors[edit]

Calculation of D[edit]

Each magic tier has an inherent mutliplier value M.
Each magic spell has a base value V.
Let dINT be (Caster's INT - Target's INT).
(Banishes and Holy, substitute MND for INT).

For dINT < 0: D = V + dINT (when dINT is a penalty, the tier mult. is always 1)
For dINT > 0, but less than some inflection point: D = V + (dINT * M)
For dINT > 0, but after some inflection point: D = V + (const + (dINT-const) * M / 2))
(above some critical value, adding INT/MND becomes half as effective)
For dINT > 0, but after some cap: D = cap

Elemental Magic:

M = 1.0 for all Helix spells.
M = 1.0 for all Ichi and Ni Ninjutsu spells.
M = 1.0 for all tier I/II single-target spells.
M = 1.0 for all -ga spells up to Blizzaga II.
M = 1.0 for all -ra spells up to Aerora II.
M = 1.5 for all San Ninjutsu spells.
M = 1.5 for all tier III single-target spells.
M = 1.5 for all -ga spells Thundaga II and beyond.
M = 1.5 for all -ra spells Fira II and beyond.
M = 2.0 for all tier IV and Ancient Magic spells.
M = ~2.299 for all tier V single-target spells.
M = 2.3 for Comet and all -ja spells. [except Aeroja and Impact, which is 2.3 repeating, see tests]

Divine Magic:

M = 1.0 for Banish and Banish II.
M = 1.0 for Banishga and Banishga II.
M = 1.0 for Holy.
M = 1.5 for Banish III.

V values by spell:

Spell Earth Water Wind Fire Ice Thunder Dark Light
I 10 16 25 35 46 60 N/A 14
II 78 95 113 133 155 178 N/A 85
III 210 236 265 295 320 345 N/A 198
IV 381 410 440 472 506 541 N/A N/A
V 626 680 738 785 828 874 963 N/A
VI Information Needed Information Needed Information Needed Information Needed Information Needed Information Needed N/A N/A
I-ga 56 74 93 120 145 172 N/A 50
II-ga 201 232 266 312 350 392 N/A 180
III-ga 434 480 527 589 642 697 N/A N/A
-ja 719 782 844 902 953 1004 N/A N/A
I-ra 128 153 179 216 247 282 N/A N/A
II-ra 317 356 396 450 496 544 N/A N/A
AM I 577 630 552 657 526 603 939 125
AM II 710 710 710 710 710 710 N/A N/A
Helix 25 25 25 25 25 25 25 25
Ichi 10 10 10 10 10 10 N/A N/A
Ni 78 78 78 78 78 78 N/A N/A
San 105 105 105 105 105 105 N/A N/A



Any equipment with "Magic Damage +" statistic as well as the bonus from Cascade has this value added to D at this point.

Multiple-Target Damage Reduction[edit]

single-target spells = 1.0
-ga spells on a single target = 1.0
-ga spells on 2 to 9 targets = 0.9 - 0.05T where T = number of targets
-ga spells on 10+ targets = 0.4
(Also applies to -ja spells)

Note: Magical Blue Magic spells Verification Needed and all AoE magical Blood Pacts are not subject to the multi-target damage penalty. It is unknown if Manifestation Drain is affected by this penalty.

Resist[edit]

resist = 1, 1/2, 1/4, 1/8, or 1/16

Staff Bonus[edit]

See Magic Affinity.

Day of the Week | Weather Bonus[edit]

Day | Weather Bonus is calculated as:

plus approximately a 1/3 chance for one of the following:

  • +0.1 for magic of the day
  • -0.1 for magic weak to the current day

plus approximately a 1/3 chance for one of the following:

  • +0.1 for magic matching single weather
  • -0.1 for magic weak to single weather
  • +0.25 for magic matching double weather
  • -0.25 for magic weak to double weather

The day and weather components are guaranteed to take effect when wearing an obi matching that day or weather.
Helix spells calculate day and weather bonuses at 100% at all times regardless of equipment. Weather spells do stack with natural weather and day but not beyond the natural cap of 20 for double weather and 10 for day. Also of note is this effect can work against you as weather and day of the opposing element will negatively impact your helix damage even with weather of the supporting element active in the spell form.
While DWB can only naturally reach 1.35, Zodiac Ring and Twilight Cape can raise it to 1.43 if equipped together on matching day with double weather.

Magic Burst Bonus[edit]

MB bonus is 1.0 for no MB and 1.3 for a 2-WS renkei, gaining 5% per extra WS in the renkei series (i.e. 1.35, 1.4 etc)
Sorcerer's Gloves multiply the magic burst bonus by 1.05.
Static Earring multiplies the magic burst bonus by 1.05.
ex. floor(floor(floor(floor(... * MB) * Sorc.Gloves) * St.Earring) * ...) -> floor(floor(floor(floor(... * 1.3) * 1.05) * 1.05) * ...)

Magic Attack Bonus / Magic Defense Bonus[edit]

MAB is divided by MDB.

MAB is as we know it (i.e. MAB I = 1.2, MAB II = 1.24 etc). Items with the description "Magic Atk. Bonus"+X means to add X/100 to the current MAB. For example, Moldavite Earring which states "Magic Atk. Bonus"+5 means to add 0.05. Correct element potency merits are +2 MAB per merit, which adds 0.02.

MDB is 1.0 if not present and depends on the target of the magic.

After calculating the ratio of MAB to MDB, this term is truncated to two decimal places. Verification Needed

Target Magic Damage Adjustment[edit]

Target Magic Damage Adjustment means exactly what it sounds like. Certain targets are designed to take more or less % damage. Values for this portion of the equation appear to use the 256 number system. The base value is 1 (256/256) and is adjusted according to the fractional values in the charts below. The values are added together in the presence of more than one adjustment.
ex. Ahriman have a TMDA value of (1 - 64/256) = 192/256
ex. An Evil Weapon with Shell has a TMDA value of (1 - 32/256 - 24/256) = 200/256
Note: For player targets, this value is capped at 128/256 (50%).

Monster Base Adjustment (%) Adjustment (256ths)
Ahriman 75% -64/256
Flans 125% +64/256
Cardians 75% -64/256
Corse 75% -64/256
Demons 75% -64/256
Evil Weapons 87.5% -32/256
Ghrahs 87.5% -32/256
Magic Pots 50% -128/256
Lamiae 87.5% -32/256
Effect Base Adjustment (%) Adjustment (256ths)
Shell 90.6% -24/256
Shell II 85.9% -36/256
Shell III 81.2% -48/256
Shell IV 78.1% -56/256
Shell V (1 merit) 75.8% -62/256
Shell V (2 merits) 75% -64/256
Shell V (3 merits) 74.2% -66/256
Shell V (4 merits) 73.4% -68/256
Shell V (5 merits) 72.6% -70/256
Bubble Curtain 50% -128/256
Shining Ruby 96% -10/256
Player Equipment varies varies




Helixes[edit]

Follow the same rule as above but the initial Damage dealt is repeated a number of times in 10 second intervals. Weather seems to have little to no effect on duration.

Sources[edit]

http://www.bluegartrls.com/forum/viewtopic.php?p=297899#297899
http://ffxi.allakhazam.com/db/jobs.html?fjob=3;mid=1137029463237848499;num=50;page=1
http://ff11.s101.xrea.com/index.php?%B4%F0%C1%C3%C3%CE%BC%B1#content_1_7
http://robonosto.blogspot.com/2008/09/magic-damage-calculations.html
http://killingifrit.com/forums/index.php?showtopic=166362
http://www.killingifrit.com/forums/index.php?showtopic=167595

Links[edit]

http://bash74.com/magic/

This article uses material from the "Calculating_Magic_Damage" article on FFXIclopedia and is licensed under the CC-BY-SA License.