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 Grade 4 is the lowest of all ranks. If traditional weapons were used against curses, Grade 4 Cursed Spirits would be easy work with a wooden bat. Grade 3 is the second-lowest level of the power scaling system. If traditional weapons were used against curses, a pistol should be enough to kill Grade 3 Cursed Spirits. Semi-Grade 2 is the first of two semi ranks. Semi-Grade 2 is close to Grade 2 in terms of strength but is not considered as high as the standard Grade 2 ranking.
 * -|Grade 4=
 * -|Grade 3=
 * -|Grade 2=

Grade 2 is the middle rank of the power scaling system and is considered the average level of Jujutsu Sorcerers. If traditional weapons were used against curses, using a shotgun would be cutting it close. Semi-Grade 1 is the second of the semi ranks. It should be noted that from this point on, the difference in power is far great between ranks than it was on previous levels. Semi-Grade 1 Jujutsu Sorcerer's are considered to be stronger than Grade 2, but still a far cry from Grade 1.
 * -|Grade 1=

Grade 1 sorcerers are considered the upper class of Jujutsu Sorcerers and the standard for all sorcerers and the top brass fit. They are paid the most and relied on to take the toughest missions.

If traditional weapons were used against curses, even a tank might be useless against a Grade 1 Cursed Spirit
 * -|Special Grade=

Special Grade
Special Grade is a rare ranking given to anomalies with an unnatural amount of power, even for a sorcerer. In 2017, there were only four registered special grade sorcerers and sixteen special grade cursed spirits.

If traditional weapons were used against curses, it would take carpeting explosives such as a cluster bomb to take down Special Grade Cursed Spirits.

In recent times, curses have begun to surpass the Special Grade ranking and many more unregistered special grades have begun appearing. A Finger Bearer is considered to be a special grade, but its power pales in comparison to Sukuna, who is also considered special grade. Satoru Gojo believes it won't be long before sorcerers and cursed spirits surpass the special grade level altogether.

Ranking
The Library has made its own power scaling system that ranks Authors, Characters, Horrors, Weapons, Armor and Story/Inner Worlds on a scale from E-Rank to Number. An Author's rank corresponds to the level of difficulty of missions and Story/Inner Worlds they can be sent to and have a theoretical chance of completing without trouble, meaning that typically Authors will be sent on missions to deal with Horrors and Story/Inner Worlds on their same level of ability. Ranks are obtained from the assessment of the Library, based on the strength and functionality of their capabilities and how well the Author can adapt and perform under stressful situations. Ranks are divided from D to ★ with the usual plus/minus modifiers for the letter ranks, so even at a young age, Authors with a ★ Rank can easily destroy low-ranking Angels and lay siege to a Heaven by themselves.
 * 1) Note: There's also the EX rank, which is shorthand for "unclassifiable", due to their nature, simply don't fit on the Ranking scale.
 * 2) Note: For people who have achieved feats beyond that, like the sisters Yue and Cero, they get numbers Three and Zero, respectively. There are only 72 known Authors with numbers which go from thirteen to zero and the closer your number is to Zero the stronger and more amazing your achievements are.

Here are the Ranks in order from low to high:  Rank D is the lowest of all ranks. Weapons like tank rounds and ICBMs can effortlessly defeat E Rank monsters in one hit. Authors of this rank are considered incredibly weak and cannot maintain their created weapons, items, armor or characters for more than a few minutes at a time and their Story/Inner Worlds are typically easy to break out of and detect. Even though they are considered weak within the physical multiverse, inside of a Story they can generate attacks of that can destroy small portions of the Ocean of Dreams and considered a small living multiverse.
 * -|Rank D=


 * -|=Rank C is the second-lowest level of the power scaling system. At this rank it would take the entire combined destructive potential of the world's collection of nukes three times over to take down a Horror of this level in one-shot. Vastly superior in strength and capability compared to a lowly D rank Author.

Rank B is considered the Rank for average Librarians and Horrors, it is around this rank when threats to humanity become more common and must be dealt with immediately. Luckily, Horrors and monsters of this rank usually hold themselves up in a fortified dungeon that they create with their powers over reality. Rank Bs purportedly destroy a galaxy with in seconds if they felt like it.
 * -|Rank B=

Rank A is the highest rank typically achieved by commoners and Earthly monsters. Horrors and Authors of this level are threats to the universe due to them being so powerful at this rank they could feasibly end the universe with one powerful attack. Most Librarians are around this level. Rank S is the standard rank of clan members and mini-boss level Horrors. It should be noted that from this point on, the difference in power is far greater between ranks than it was on previous levels. S-Rank Authors are considered to be stronger than A-Rank Authors, but still a far cry from EX-Rank Authors. They are ten times stronger than A-Rank Authors in the physical multiverse and their will's are able to influence the physical multiverse with ease.
 * -|Rank A=
 * -|Rank S=


 * -|Rank EX=

Rank EX Authors are considered the cream of the crop and the standard for which the top brass and most seasoned professors in the Library fit. They are paid the most and relied on to take the toughest missions. Their power is generally so vast and powerful they cannot be sensed by normal means and is generally unquantifiable by regular means.
 * -|★ Rank=

★ Rank
★ Rank is a rare ranking given to anomalies with an unnatural amount of power, which even dwarfs the power of EX Rank Authors many times over. In 2017, there were only 101 registered ★ Rank Authors and forty-six ★ Rank items and characters.

Horrors of this rank are beings of unfathomable strength, typically leaders of major organizations and have extremely powerful abilities & weapons at their disposal. An entire team including at least two ★ Rank Authors are suggested for hunting them.

In recent times, both Authors and Horrors have begun to surpass the ★ ranking and many more unregistered ★ Rank Horrors have begun appearing.
 * -|Number=

Number
Number the rarest and most dangerous beings. Only two characters in the series hold this rank, being the Big Bad and Big Good, respectively. Operations to challenge them are the largest in scale, often making use of an entire squad of Special Class Investigators and the best equipment available.