Weak toGroundGhostFireDark ×1.6

Attacker	Type	Moveset	DPS
Blacephalon	FireGhost	IncinerateMind BlownLegacy	49.5
Reshiram	DragonFire	Fire FangFusion FlareLegacy	41.1
Chandelure	GhostFire	Fire SpinOverheat	37.6
Cinderace	Fire	Fire SpinPyroball	37.1
Volcarona	BugFire	Fire SpinOverheat	36.7
Darmanitan	Fire	Fire FangOverheat	36.6
Darkrai	Dark	SnarlShadow Ball	36.0
Gengar	GhostPoison	LickShadow BallLegacy	35.6
Blaziken	FireFighting	Fire SpinBlast BurnLegacy	35.4
Groudon	Ground	Mud ShotPrecipice BladesLegacy	35.3
Moltres	FireFlying	Fire SpinOverheat	35.0
Absol	Dark	SnarlBrutal SwingLegacy	34.9

Clear boosts the Fire attacks above. Snow and Windy boost Beldum.

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

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

Questions people ask

What is Beldum weak to in Pokémon GO?

Beldum takes 1.6 times from Ground, Ghost, Fire and Dark.

What's the best counter to Beldum?

Blacephalon with Incinerate and Mind Blown, worth 49.5 damage per second against Beldum's own defense. The full ranking is above.