Arm warmers (or arm socks) are knitted 'sleeves' worn on the arms. Usually worn by dancers to warm up their bodies before class, they have also become somewhat of a fashion item, appearing in the fall. These arm warmers are virtually identical in fabric and style as those worn by dancers.

Arm warmers can also describe any glove-like articles of clothing that lack finger coverings and/or were originally designed to keep wrists and lower arms warm. Today, many competition and sport bicyclists wear spandex-compression arm-warmers.

Various sub-cultures, such as the punk and goth subcultures, have also adopted arm warmers as a fashion statement.