Pour about 3 inches of water into a large stockpot and bring it to a boil over medium-high heat.
If needed, crack the crab legs slightly using seafood crackers or kitchen shears to make them easier to eat.
Arrange the crab legs inside the pot or a steamer basket.
Cover and steam for 5–7 minutes until heated through. If using raw crab legs, cook for 10–12 minutes until the shells turn bright red-orange and the meat is opaque.
Carefully remove the crab legs and keep them warm.
Discard the steaming water and return the pot to the stove over medium heat.
Melt the butter, then add the minced garlic. Cook for about 30 seconds until fragrant.
Stir in the salt, black pepper, and chopped parsley.
Return the crab legs to the pot and gently toss until evenly coated in the garlic butter sauce.
Transfer to a serving platter and garnish with additional parsley and fresh lemon wedges.
Serve your Crab Legs with Garlic Butter immediately while hot.