Player Customization is a gameplay feature in the Call of Duty series that allows the player to customize their character's appearance with cosmetic changes and additions. Player customization originated with Face Paint in Call of Duty: Black Ops, eventually broadening to general player customization in Call of Duty: Ghosts and remaining a part of gameplay since. Player customization allows the player to change their character, clothing, model, voice, race, and emotes, depending on the available items in a given title. Player customization is used to customize the player's character, Specialist or Combat Rig, and individual pieces are earned through progression and challenges, supply drops and other microtransactions, promotions and as Battle Pass rewards.
In Call of Duty: Ghosts, Call of Duty: Advanced Warfare, Call of Duty: Modern Warfare Remastered and Call of Duty: WWII, player customization involves the general customization of a generic player character with universal cosmetics and individual customizable features. In Call of Duty: WWII specifically, some items are universal to all characters, whereas some items are unique to a specific Division.
In Call of Duty: Black Ops III, Call of Duty: Infinite Warfare, Call of Duty: WWII, Call of Duty: Black Ops 4 and Call of Duty: Modern Warfare, player customization involves the customization of the player's unique character with customization pieces obtained through completing challenges, promotions, supply drops, microtransactions and battle pass unlocks. These customization options are all unique to the specific character they choose, except in the case of WWII, where only some of the items are unique.