A Pokémon's power can be determined by many different factors. Their base stats determine how naturally strong a Pokémon can be, but there are many categories that Pokémon fit into.
Normal
Arceus is the strongest normal-type Pokémon with the highest base stat total of all Pokémon in their base forms. There were 120 base stats for each of his stats for a total of 720. He is able to change his strike when holding different plates, but his default form is normal.
Slaking is the strongest non-legendary normal-type Pokemon with a total base stat of 670. It is held back by its Truant ability and can have its ability suppressed by various means in battle.
Mega Lopunny is the strongest normal Mega evolution with a total base stat of 580.
Fighting
Zamazenta is the strongest Fighting-type Pokemon with a base stat total of 670. Its crowned shield form changes its stats and increases its base stat total to 720. It lowers its base speed stat by 10 and increases his Defense and Special Defense stats by 30 each while in this form.
Kommo-o is the strongest non-legendary fighting-type Pokémon with a total of 600 base stats. The Pokemon is considered a pseudo legendary by fans of the series. Marshadow has the same number and is considered a Mythical Pokemon.
Mega Mewtwo X is the strongest Mega Fighting-type Pokémon with a base stat total of 780. It is tied for the second-highest base stat total between Rayquaza and Mega Mewtwo Y.
Feu
Primal Groudon is the strongest Fire-type Pokémon with a total base stat of 770. Its ability blocks water moves, effectively removing its 4x weakness.
Arcanine is the strongest non-legendary fire-type Pokémon with a total base stat of 555.
Mega Charizard X and Mega Charizard Y are the most powerful Mega Fire-type Pokemon with a total base stat of 634.
Related: Best Fire-type Pokémon in Pokémon Go
Water
Primal Kyogre is the strongest water-type Pokemon with a total base stat of 770.
Wishiwashi in his school form is the strongest non-legendary water-type Pokémon with a total base stat of 620. This is reduced to 175 when in his solo form.
Mega Gyarados is the strongest Water-type Mega Pokémon with a base stat total of 640. Although not a Mega, Ash Greninja is tied with that total.
Herbe
Celebi, Shaymin, Shaymin Sky Forme, and Zarude tied for the most powerful Grass-type Pokémon with a total of 600 base stats. Celebi, Zarude, and Shaymin Sky Forme both have 4x weaknesses, giving Shaymin the edge when it comes to survivability.
Tangrowth is the strongest non-Legendary Grass-type Pokémon with a total base stat of 535.
Mega Sceptile is the strongest Grass-type Mega Pokémon with a total base stat of 630. Mega Venusaur is only five points behind it and has no 4x weakness to Ice.
Poison
Eternamax Eternatus and Eternatus are the strongest Poison-type Pokémon with a total base stat of 1125 and 690, respectively.
Naganadel is the strongest non-legendary poison-type Pokemon with a total base stat of 540. This Pokemon is an Ultra Beast, making it the next highest non-Ultra Beast Pokemon, Crobat with 535.
Mega Gengar is the strongest Poison-type Mega Pokemon with a total of 600 base stats.
Bug
Genesect, Mega Scizor, Mega Pinsir, and Mega Heracross all tied for the strongest Bug-type Pokémon. Genesect is considered a Mythical Pokemon and all three Megas are boosted by 100 points from their base form to a total of 600 base stats.
Pheromosa and Buzzwole are tied for the strongest non-Legendary, non-Mega Bug type Pokémon with a total base stat of 570. Golisopod is the next strongest that isn't an Ultra Beast with a total stat of basis of 530.
Flying
Rayquaza, Yveltal, Lugia, and Ho-oh are the strongest flying-type Pokémon with a total base stat of 680. Rayquaza's Mega increases it to 780, on par with Mewtwo's two Mega Evolutions.
Dragonite, both Shaymin forms, both Landorus forms, and Salamence are tied for the strongest non-Legendary Flying-type Pokemon with a total of 600 base stats.
Mega Salamence is the strongest non-legendary flying-type Pokemon with a total of 700 base stats.
Electric
Zekrom is the strongest Electric-type Pokemon with a total base stat of 680. Zeraora follows that with 600 as a Mythical Pokemon.
Electivire is the strongest non-Legendary Electric-type Pokémon with a total base stat of 540.
Mega Manectric is the strongest Mega Electric-type Pokemon with a total base stat of 575.
Salt
Primal Groudon is the strongest ground-type Pokémon with a total base stat of 770. Following this is Complete Zygarde Forme at 708.
Garchomp is the strongest non-legendary ground-type Pokemon with a total base stat of 600 and is on par with both forms of Landorus. All three Pokémon share a 4x weakness with Ice.
Mega Garchomp is the powerful Mega Ground type Pokémon with a total of 700 base stats.
Roche
Both Tyranitar and Diancie are tied for the strongest Rock-type Pokemon as they share a total of 600 base stats. They are both capable of Mega Evolving as well, increasing their stats to 700.
Related: Best Rock-type Pokémon in Pokémon Go
Ice
Black and White Kyurem are the strongest Ice-type Pokémon with a total of 700 base stats. Below is Ice Rider Calyrex at 680.
Lapras and Vanilluxe tied for the strongest non-legendary ice-type Pokémon with a base stat total of 535.
Mega Abomasnow is the strongest Mega Ice-type Pokemon with a total base stat of 594.
Psychic
Ultra Necrozma is the strongest Psychic-type Pokémon with a total base stat of 754. The next strongest Pokémon are Mewtwo, Hoopa Unbound, Solgaleo, Lunala, the two Calyrex Rider Forms, and the other two Necrozma forms in Dawn Wings and Dusk Mane with a total of 680 base stats.
Metagross is the strongest non-Legendary Psychic-type Pokémon with a total of 600 base stats.
Mega Mewtwo X and Y are the strongest Mega Psychic type Pokémon with a total base stat of 780. Mega Metagross is the strongest non-Legendary Mega Psychic type with a total of 700 base stat.
Ghost
Dawn Wings Necrozma, Lunala, Shadow Rider Calyrex, and both Giratina forms tied for the most powerful Ghost-type Pokémon with a base stat total of 680.
Marshadow and Dragpult are the strongest non-Legendary Ghost-type Pokémon with a total of 600 base stats.
Mega Gengar is the strongest Mega Ghost-type Pokémon with a total of 600 base stats.
Dark
Yveltal and Hoopa Unbound are tied for the most powerful dark-type Pokémon with a base stat total of 680.
Zarude, Hyrdreigon, and Tyranitar tied for the strongest non-Legendary Dark-type Pokémon with a total of 600 base stats.
Mega Tyranitar is the strongest Mega Dark type Pokemon with a total of 700 base stats.
Dusk Mane Necrozma is the strongest steel-type Pokémon with a total base stat of 754. Crowned Sword Zacian and Crowned Shield Zamazenta are the next strongest steel-type Pokémon with a total base stat of 720. That's 50 points higher than their Hero of Many Battles form.
Metagross, Melmetal, Magearna, and Genesect tied for the strongest non-legendary steel-type Pokémon with a total of 600 base stats.
Mega Metagross is the strongest Mega Steel-type Pokemon with a total of 700 base stats.
Dragon
Eternamax Eternatus and Eternatus are the most powerful Dragon-type Pokémon with a total base stat of 1125 and 690, respectively.
Dragapult, Salamence, Dragonite, Garchomp, Hydreigon. Goodra and Kommo-o all tied for the highest non-legendary dragon-type Pokemon with a base stat total of 600.
Mega Salamence and Mega Garchomp are the strongest non-legendary Mega Dragon-type Pokémon with a total of 700 base stats. Mega Rayquaza is the strongest Mega Dragon-type Pokémon with a total base stat of 780.
Fairy
Crown Sword Zacian is the strongest Fairy-type Pokémon with a total base stat of 720. The second highest is Xerneas and Solgaleo at 680.
Diancie and Magearna are the strongest Mythical Fairy-type Pokémon with a total of 600 base stats. Florges follows this as a non-Mythical Pokemon at 552.
Mega Diancie is the strongest Mega Fairy-type Pokemon with a total of 700 base stats. Mega Gardevoir follows this as the strongest non-mythic Mega with a base stat total of 618.
While this shows the strongest Pokemon by base stats, there are other factors that can determine a Pokemon's effectiveness in battle. Strategy and practice can cause even a level one Rattata to take down the strongest of legendaries.
For more Pokémon guides, check out Which Pokémon Should I Get: Shiny Diamond or Shiny Pearl? on Pro Game Guides.
