Details of the life of Namdev are vague.He is traditionally believed to have lived between 1270 and 1350 but S. B. Kulkarni — according to Christian Novetzke, "one of the most prominent voices in the historical study of Maharashtrian sant figures" — has suggested that 1207-1287 is more likely, based on textual analysis. Some scholars date him to around 1425 and another, R. Bharadvaj, proposes 1309-1372.
Namdev was married to Rajai and had a son, Vitha, both of whom wrote about him, as did his mother, Gonai. Contemporary references to him by a disciple, a potter, a guru and other close associates also exist. There are no references to him in the records and inscriptions of the then-ruling family and the first non-Varkari noting of him appears possibly to be in the Lilacaritra, a Mahanubhava-sect biography dating from 1278. Smrtisthala, a later Mahanubhava text from around 1310, may also possibly refer to him; after that, there are no references until a bakhar of around 1538.[11][a]

According to Mahipati, a hagiographer of the 18th century, Namdev's parents were Damashet and Gonai, a childless elderly couple whose prayers for parenthood were answered and involved him being found floating down a river. As with various other details of his life, elements such as this may have been invented to sidestep issues that might have caused controversy. In this instance, the potential controversy was that of caste or, more specifically, his position in the Hindu varna system of ritual ranking. He was born into what is generally recognised as a Kshatriyas caste, variously recorded as shimpi (tailor) in the Marathi language and as Chhipa, Chhimpa,Chhimba,chimpi (calico-printer) in northern India. Shudra is the lowest-ranked of the four varnas and those of his followers in Maharashtra and northern India who are from those communities prefer to consider their place, and thus his, as the higher-status Kshatriya rank.[13][12]

There are contrary traditions concerning his birthplace, with some people believing that he was born at Narsi Bahmani, on the Krishna River in Marathwada, and others preferring somewhere near to Pandharpur on the Bhima river.[14] that he was himself a calico-printer or tailor and that he spent much of his life in Punjab.[7][15] The Lilacaritra suggests, however, that Namdev was a cattle-thief who was devoted to and assisted Vithoba.[16][15][b]

A friendship between Namdev and Jñāneśvar, a yogi-saint,[18] has been posited at least as far back as circa 1600 CE when Nabhadas, a hagiographer, noted it in his Bhaktamal.[7] Jñāneśvar, also known as Jñāndev, never referred to Namdev in his writings but perhaps had no cause to do so; Novetzke notes that "Jnandev's songs generally did not concern biography or autobiography; the historical truth of their friendship is beyond my ken to determine and has remained an unsettled subject in Marathi scholarship for over a century."[19]

Namdev is generally considered by Sikhs to be a holy man (bhagat), many of whom came from lower castes and so also attracted attention as social reformers. Such men, who comprised both Hindus and Muslims, traditionally wrote devotional poetry in a style that was acceptable to the Sikh belief system.[15]

A tradition in Maharashtra is that Namdev died at the age of eighty in 1350 CE.[7] Sikh tradition maintains that his death place was the Punjabi village of Ghuman, although this is not universally accepted. Aside from a shrine there that marks his death, there are monuments at the other claimant places, being Pandharpur and the nearby Narsi Bahmani