The Gandhi cap (Hindi: गाँधी टोपी) is a white sidecap, pointed in front and back and having a wide band. It is made out of khadi. It takes its name after the Indian leader Mahatma Gandhi, who created it and first popularised its use during the Indian independence movement.

Worn commonly by Indian independence activists, it became a symbolic tradition for politicians and political activists to wear in independent India.

Gandhi, in a conversation with Kaka Kalelkar, described how he created the Gandhi cap. Gandhi said that he looked at a number of caps from various parts of India and wanted to design a cap that would cover the head in hot weather and would be easy to keep in a pocket. He found Kashmiri cap to be coming close to what he wanted to design but it used wool. Gandhi writes that he instead used cotton cloth in white because white clothes are supposed to be washed more regularly and are easier to wash.

The Gandhi cap emerged in India during the Non-cooperation movement from 1920 to 1922, when it became the standard Indian National Congress dress as popularized by Gandhi.

By 1920, a substantial number of Indian males wore this cap. Colonial officials in the Central Provinces banned Indian Civil Service employees from wearing Gandhi caps.

Gandhi's homespun khadi attire of traditional Indian clothes were symbolic of his message of cultural pride, the use of Swadeshi goods (as opposed to those manufactured in Europe), self-reliance and solidarity with India's rural masses. The cap became common to most followers of Gandhi and members of the Indian National Congress. A connection to the independence movement was implied when any individual wore the cap in those times.

Black prisoners in South African prisons were required to wear a small headcover during the early 20th century. This has been cited as the genesis of the Gandhi Cap.

The Gandhi cap was also adopted by the members of Rashtriya Swayamsevak Sangh (RSS).^{[citation needed]}