"Buddhism and Jainism were not related to each other as parent or child but rather children of common parent, born at different intervals, though at about the same period of time and marked by distinct characteristics, though possession a strong family of resemblances". W.W. Hunter writes "Jainism is as much independent from other sects, specially from Buddhism as can be expected, from any other sect.
Not withstanding certain similarities, it differ from Buddhism in its ritual and objects of workship."
Similarities :
(1) The source of both the religion is vedic religion and both and indebted to Upanishads
(2) Both Gautam Buddha and Mahavir belonged to princely families and not to priestly families.
(3) Both deny the existence of God.
(4) Both denied the authority of the Vedas and the necessity of performing sacrifices and rituals.
(5) Both have accepted the theories of Karma rebirth and Moksha.
(6) Both taught in the language of the common people i.e. Prakrit and not in Sanskrit which was the language of the priests.
(7) Both of them were opposed to animal sacrifices.
(8) Both of them admitted disciples from all the castes and from both sexes.
(9) Ahimsa is the prominent principle of both the religions.
(10) Both Buddhism and Jainism put stress on right conduct and right knowledge and not on religious ceremonial and ritual as the way to obtain salvation.
(11) Both, the religions came as a sort of reform of Hindu religion.
(12) Both the Religions were later on divided into two sects. Buddhism was divided into Mahayana and Hinayana. Jainism was divided into Svetambara and Digambara.
(13) Both had their own three gems or 'Tri Ratna'. Tri Ratna of Jainism were right philosophy right knowledge and right character. The Tri-Ratna of Buddhism were Budhha, Dhamma and Sangha.
(14) Both had three main religious texts. Tripitaka, i.e. Vinaypitak, Suttapitaka