Individual values – bulbapedia, the community-driven pokémon encyclopedia static electricity review worksheet

Individual values (Japanese: 個体値 individual values), abbreviated IVs, and sometimes referred to as determinant values (DVs) in the context of Generations I and II, are the Pokémon equivalent of genes. They are instrumental in determining the stats of a Pokémon, being responsible for the large variation in stats among untrained Pokémon of the same species.

Each of the six battle stats has an IV associated with it, with that IV coming into calculation alongside the Pokémon’s base stats, Nature, and EVs to determine the actual stat number. A Pokémon’s IVs are fixed when it is generated by the game (i.e. when it is obtained as an Egg from the Pokémon Day Care, encountered in the wild, or given to the player by an NPC), and cannot be changed (although Hyper Training causes stats to become values corresponding the maximum IVs).

IVs have been officially known as 生まれつきの強さ innate strengths in Japanese since at least Pokémon Gold and Silver. In English, recent media from The Pokémon Company International has called them individual strengths. [1] [2] In the games, the term potential is often used to allude to IVs, such as by the stats judge. Shigeru Ohmori has stated that the reason EVs and IVs are hidden is because he prefers to think of Pokémon as "real, living creatures". [3]

In Generation I and II, only four IVs are stored for each individual Pokémon: Attack, Defense, Speed, and Special. Each of these is used to determine their associated stat, with the HP IV determined from the IVs stored for the other four. IVs range from 0-15 (in binary 0000-1111).

The HP IV is calculated by taking the least significant bit (the final binary digit) of the Attack, Defense, Speed, and Special IVs, then creating a binary string by placing them in that order. As such, a Pokémon with an odd-number Attack IV has 8 added to its HP IV, an odd-number Defense IV has 4 added, an odd-number Speed IV has 2 added, and an odd-number Special IV has 1 added.

In Generation II, a Pokémon’s gender is determined based solely on its Attack IV when compared to a value specific to each Pokémon species. A Pokémon is female if its Attack IV is less than or equal to its species’ gender code, otherwise it is male. For species that are exclusively one gender or have no gender, the calculation based on the Attack IV is ignored.

Due to this calculation, it is impossible to obtain a female Pokémon with high Attack, unless the Pokémon is a member of an all-female species like Jynx or Chansey. Starter Pokémon and others with a gender ratio of seven males to one female suffer the most, with the maximum Attack IV for a female Pokémon of those species being 1.

Except when IVs are influenced due to breeding, this set of IVs has a 1/8192 chance of occurring, which is also the likelihood of a wild Pokémon being Shiny in Generation III, IV, and V. Due to HP IV being calculated from the other IVs, a Shiny Pokémon’s HP IV can only be 0 (if the Attack IV is even) or 8 (if the Attack IV is odd).

In Generation II, Unown’s letter is taken from the combination of the center two bits of the Attack, Defense, Speed and Special IV nibbles. This combination is then divided by ten, and the result is rounded down ( floor[]) to only include the integer part of the number. This integer will range from 0-25, corresponding to a letter in the Latin alphabet, which will be the Unown’s letter (where 0=A, 1=B, 2=C, …, 23=X, 24=Y, 25=Z).

In Generation II, due to this method of calculating Unown’s letter and the way that Shiny Pokémon are determined, a Shiny Unown can only exist in the shape of the letter I or V. Additionally, due to this method of calculating Unown’s letter, only 6 combinations correspond to Unown Z, whereas 10 combinations correspond to every other Unown, making Unown Z less common.

The calculated Type and Power of the move Hidden Power is based on the IVs of the Pokémon. Hidden Power can be of any type aside from Normal, and can have a power between 31 and 70. The formula used in Generation II is different to the one used in later generations.

The move’s type is determined by the two least significant bits of the Attack and Defense IVs. The move’s power is determined by the most significant bit of each of the Pokémon’s IVs, as well as the two least significant bits of the Special IVs.

Since IVs now have twice the range, they now have half the influence on a Pokémon’s stats. The EV system overhaul and the addition of Natures also result in small changes to formula used to determine stats. The personality value was introduced in Generation III, which handles a Pokémon’s gender and Shiny status instead, as well as several other properties; in Generation III, Unown’s form was also handled using the personality value, but this is stored separately in Generation IV onward.

• In Pokémon Sun and Moon, if the player has hatched 20 Eggs, an Ace Trainer standing by the Battle Tree receptionist will upgrade the Pokémon Storage System with the Judge program. The Judge program will show a graph of how IVs are placed and a comment on the overall numbers.

From Generation IV onward, each Pokémon has a characteristic, a small blurb that indicates which of the Pokémon’s IVs is the highest in a roundabout way. Rather than explicitly stating it, one of 30 of these short sentences is chosen, depending on which of the six stats the highest IV is in and how much more than a multiple of five it is.

In Pokémon X and Y, all Pokémon in the Undiscovered Egg Group are guaranteed to have a perfect 31 in at least three of their individual values when caught in the wild or obtained as a gift (except via Mystery Gift). In Pokémon Omega Ruby and Alpha Sapphire, this only applies to Legendary and Mythical Pokémon. In Generation VII, this applies to Legendary Pokémon, Mythical Pokémon, and Ultra Beasts.

In Pokémon Sun and Moon, Hyper Training allows the player to make a Pokémon’s stats act as if the Pokémon had maximum IVs. However, this does not actually change the IVs, so its true IVs are still used for the purposes of Hidden Power and breeding.

In Generation III, the most significant bit specifies which of two Abilities a Pokémon has (if it has potential to have more than one). If the Pokémon’s species can have only one Ability in Generation III, the Ability bit is forced to 0 by the game (if it is forced to be 1, "No ability" will be listed as the Pokémon’s Ability).

In Generation IV onward, the most significant bit instead specifies whether or not the Pokémon is nicknamed, while the second-most significant bit fulfills the same role as in Generation III. This allows an unnicknamed Pokémon traded to a game of a different language to retain its name in the language of the previous game, but still change its name upon evolution.

In Pokémon GO, IVs have a range of 0 to 15. Pokémon have an IV for each of their three basic stats: HP, Attack, and Defense. In Pokémon GO, IVs are the only factor that can distinguish one Pokémon’s stats from another’s of the same species if they have the same Power Up level.