Weak toFighting ×1.6

Attacker	Type	Moveset	DPS
Lucario	FightingSteel	Force PalmAura SphereLegacy	40.9
Pheromosa	BugFighting	Low KickFocus Blast	37.4
Terrakion	RockFighting	Double KickSacred SwordLegacy	37.2
Blaziken	FireFighting	CounterAura Sphere	37.0
Kartana	GrassSteel	Fury CutterSacred Sword	35.3
Conkeldurr	Fighting	Force PalmFocus Blast	34.1
Keldeo	WaterFighting	Low KickSacred Sword	33.8
Breloom	GrassFighting	Force PalmDynamic Punch	33.6
Urshifu	Fighting	CounterDynamic Punch	33.4
Eternatus	PoisonDragon	Poison JabDynamax CannonLegacy	33.2
Marshadow	FightingGhost	CounterClose Combat	32.6
Mewtwo	Psychic	CounterFocus BlastLegacy	32.5

Overcast boosts the Fighting attacks above. Partly cloudy boosts Porygon.

Level 40, 15 attack IV, costed against Porygon's own defense and typing, one per evolution family.

Porygon's moveset, CP and shiny All counters Raid board

Questions people ask

What is Porygon weak to in Pokémon GO?

Porygon takes 1.6 times from Fighting.

What's the best counter to Porygon?

Lucario with Force Palm and Aura Sphere, worth 40.9 damage per second against Porygon's own defense. The full ranking is above.