Parameter Rules

are a set of rules for representing the relative power of each item ranked by letters under different systems, translated into specific parameters "for no particular reason." 
There are five main ranks, E, D, C, B, A, that each have a quantifiable number assigned to it. Considering "one" to be a "normal value", E is equal to "ten" and it increases by ten incrementally until reaching "fifty" at A. A is the highest normal rank, but there is an exception to the rule with the EX Rank.Fate/EXTRA CCC It represents something that falls outside of the numerical ranking scale, a value that cannot be quantified under the normal system because it is in a league of its own, powerful to the extent of rendering comparisons meaningless. BB in the Moon Cell presents a special ★ category that signifies something that cannot be numerically represented rather than exceeding the limits of the system like EX. ? has been used with the Servant Noble Phantasm parameter statistic to reflect two without proper Noble Phantasms, EMIYA and Sasaki Kojirou. has been used with Li Shuwen whose No Second Strike is technically not a Noble Phantasm. — has been used to denote that the statistic does not apply, such as with Kingprotea not possessing a Noble Phantasm. Outside of normal paramaters, Human Bedivere is displayed having an "F" parameter,Fate/Grand Order THE MOVIE - Divine Realm of the Round Table: Camelot Paladin; AgateramThere is no known Parameter Rank corresponding to the letter "F", so it is unknown if this is an animation error or simply unexplained. and Servant Elizabeth Bathory (Brave) has a unique "V" parameter.Fate/Grand Order - Elizabeth Bathory (Brave) - Strengthening Quest 2
There are two different "modifiers" that can be applied to ranks, + and -. The "+" modifier represents the capacity of a temporary boost in power, allowing a weapon or ability of a lower rank to surpass a higher rank for a moment. While a B+ is generally weaker than an A, B+ may momentarily exceed A by doubling its own power. + indicates a two-times increase, ++ indicates a three-times increase, and +++ indicates a four-times increase. The "-" modifier indicates a rank which has a number that is not reliably stable, technically qualifying for that rank, but not quite reaching the rank in terms of power or ability and possibly being even closer to the next rank down.
While the ranks correspond to numbers, there may be cases where a specific rank matters more than the number it represents. The Noble Phantasms God Hand and Armor of Fafnir defend directly on the basis of rank, even though the parameters for Noble Phantasms and regular attacks differ. Converting the numbers, Noble Phantasms of C Rank are the equivalent of an A+ or A Rank regular attack, but the armor Noble Phantasms only defend according to the rank of each individual system while ignoring the equivalence.
Rank	Value	+ 	++ 	+++
A 	50 	100	150	200
B 	40 	80 	120	160
C 	30 	60 	90 	120
D 	20 	40 	60 	80
E 	10 	20 	30 	40
*Physical attacks: Physical attacks of a powerful enough nature, like those of Servants, can be ranked as such. While a sword Noble Phantasm may be A-rank, the rank is not fulfilled without activating its true power as a Noble Phantasm, so the strength of a strike instead comes from the Servant's Strength statistic. It is also possible for weapons to allow for more attacks more powerful than the wielder's Strength, such as Atalanta drawing her bow out to its limit for an attack exceeding A-rank.Fate/Apocrypha - Volume 1
*Magecraft: The amount of power that goes into a spell decides its rank, mitigated by abilities like Magic Resistance. A Rank Magecraft is already on the level of Greater Magecraft, and Magecraft of A+ Rank is said to be almost at the level of Magic.
*Servant statistics and Skills: Under the Servant system, their six statistics and main Skills are each given a rank corresponding to their overall abilities. While the Master and local attributes have some influence on them, the ranks are mostly decided by the Heroic Spirit's own abilities and fame. Due to various factors, they may be lower or higher than normal, and abilities like Mad Enhancement can increase them beyond even their optimal level. Servants with + modifiers are thought to be extraordinary. Heroic Spirits possessing A+ level attributes are rare, those possessing A++ attributes are extraordinary, those possessing A+++ attributes are in a class of their own, and those possessing EX attributes have truly exceptional abilities that fall outside of the numerical ranking scale. Gilgamesh, although not possessing very impressive scores for his overall abilities, is clearly distinguished from other Heroic Spirits due to his EX ranked Noble Phantasm parameter. Abilities will often base the effectiveness of the attack or effect directly on rank, and there are those that have "Strength Checks" or "Luck Checks."The Moon Cell's Servant system's parameters are slightly different. Their statistics are based upon the link between the souls of the Master and Servant, and that link can be increased as the Master's rank increases by hacking with performed by Aoko Aozaki. The ranks progress sequentially from: E, D, C, B, A, A+, A++, and EX.
*Noble Phantasms: Noble Phantasms follow the same general principal in terms of their ranks, but they are more of a rough concept to show comparative strength rather than specific numerical values. + modifiers still temporarily double their power for a moment. They are on a higher scale than regular attacks, with a Noble Phantasm of C Rank being the equivalent of an A+ or A Rank regular attack. A++ and EX Rank Noble Phantasms are said to be a Mystery on the level of Divine Spirits. In the case of armaments being used as physical weapons without being activated as true Noble Phantasms, their attacks are based only upon the Strength of their wielder. There are Noble Phantasms that can be quantified directly by numbers when referring to their abilities, but there are also those with conceptual effects that fall into a special category.
*Servants and Masters : Servants and Masters are granted some form of rank through unknown parameters. Heroes of the highest fame are said to almost always be A Rank Servants.Fate/stay night Fate route: Day 4 - Contract Established / Saber (I) Hakuno Kishinami is an E- Rank Master, while Rin is considered A Rank. Lancer is estimated to rank from B+ to A as a Servant, while Gilgamesh ranks at EX. If a normal A-rank Servant is "100", Caster ranks at "9."
True Name 	Rank 	Notes
Gilgamesh 	EX RankFate/EXTRA CCC - Chapter 1: Subordination Garden -Backyard of Eden- 	Summoned as a Top Servant in Fate/EXTELLA.
Achilles 	A RankFate/Grand Order - Inheritance of Glory, Section 2: Defense: Millennia Fortress 	Sieg claims Achilles is really powerful, even for an A rank.
Artoria Pendragon 	A Rank 	Summoned as a Top Servant in Fate/EXTELLA.
Charles Babbage 	A RankFate/Grand Order - Gilgamesh's 2nd Interlude: Law of Creation 	In Gilgames's 2nd interlude, Shadow Servant Babbage fights Gilgamesh. Romani Archaman claims that they are A rank.
Charlemagne 	A RankFate/Grand Order: Cosmos in the Lostbelt - Traum Singularity, Section 21: Death of a Detective 	
Chiron 	A Rank 	Sieg claims Chiron is really powerful, even for an A rank.
Heracles (Berserker) 	A Rank 	
Ishtar (Swimsuit) 	A Rank 	
Karna 	A Rank 	Summoned as a Top Servant in Fate/EXTELLA.
Zhuge Liang 	A RankFate/Grand Order - Zhuge Liang's 3rd Interlude: Truth of the Ascension 	
Elizabeth Báthory 	B+ or A Rank 	Elizabeth Báthory while suppressed is stated to be a B+ Rank servant, perhaps even A rank.
EMIYA Alter 	B RankFate/Grand Order - SE.RA.PH: Abyssal Cyber Paradise, Act III: The Nutcracker, Once More (3/3) 	
Charlotte Corday 	C Rank 	
Mandricardo 	C RankFate/Grand Order: Cosmos in the Lostbelt - Atlantis: Ancient Ocean of the Dreadnought Gods, Section 3: Enduring Light of the Gods	
Hans Christian Andersen	E Rank 	
*Magic Circuits and Regression to the Age of Gods: Magic Circuits and Regression to the Age of Gods are ranked by and . There is also an accompanying measurement that describes their overall ability instead of a letter rank.
*Humanity Foundation Value: Humanity Foundation Value is a system of ranks designated for the Human Order Foundations in Fate/Grand Order. The seven Singularities created in the Grand Orders were meant to overturn seven of the most significant Quantum Time-Locks, in other words, the Human Order Foundations, within the History of Man. Each rank represents the significance of each Quantum Time-Lock, and losing one of them will have a proportionate effect on the History of Man depending on its ranking. The greater the ranks of the Quantum Time-Locks lost, the greater the effect on the History of Man being reduced into chaos.
*Other: Characters will often use the letter grades in a non-serious manner, such as Shirou Emiya describing Rider by saying "she has a rank of A+ in terms of people I cannot get along with." Others may assign ranks to other joking characteristics such as Kiyohime describing her "cleaning skills" (as in getting rid of trash) as A+++ Rank.
==Notes==
==References==
it:Regole dei parametri
vi:Quy Tắc Thông Số
Category:Servants
Category:Magecraft terminology
Category:Terminology in Fate
Category:Holy Grail War terminology