Larian Studios Forums Baldur's Gate III Baldur's Gate III - Help Tips & Tricks How heavy armour and dexterity works?

Moving your cursor over the AC value or item should explain it. But here is the short version:

Light Armor = Full dex modifier
Medium Armor = Up to +2 dex modifier
Heavy Armor = No dex modifier

The dex modifier on armor ONLY determines its contribution to Armor Class. Your Dexterity Saving Throws and attack rolls using Dexterity ALWAYS uses your full dex modifier, even in Medium or Heavy Armor.