So once you’ve determined the stat on which you want to use vitamins, you’ll need to purchase them. Each vitamin will increase the specific stat by 10 EVs. Every Pokemon has a total of 510 EVs to be distributed among the six stats. Each separate stat can be maxed at 252, meaning you’ll need 25 vitamins of a specific stat to make it out.
In all core series games since Generation III, vitamins that affect stats increase a Pokémon's EVs for a given stat by 10 EV points, but can't increase the total EVs beyond a maximum of 510. Between Generations III and VII , vitamins will also have no effect on an individual stat that already has 100 or more EVs.
The maximum EVs a Pokémon can have in a specific stat is 252, which results in an increase of 63 in that stat when the Pokémon reaches level 100. 510 is the maximum total amount of EVs a Pokémon can have. A common method of training is to max out two stats with 252 EVs and then place the remaining 6 in another stat.
You can often max out the EVs by level 20, which leaves the Pokémon free for use in-game; it will also be stronger than normal. Don't lose Pokérus. If your Pokémon get the Pokérus, always keep a few with the virus in the PC to pass on to future Pokémon you wish to train. Use vitamins early.
RPcIUpD.