A key chain is a small, typically portable accessory used to hold and organize keys. It usually consists of a ring or loop, often made of metal, leather, or plastic, where keys can be attached. Key chains may also feature additional decorative elements such as charms, figurines, logos, or personal trinkets. They are often designed to be compact, lightweight, and functional, making it easy to carry keys together in one place.

They can come in a variety of styles, materials, and designs, making them both practical and aesthetically pleasing.