Considered to be a child prodigy, Vani Jairam is known to have recognized the different ragas of Indian classical music before the age of five. Her voice was first heard on All India Radio, Madras, at the age of eight. The fifth daughter in a family of six daughters and three sons, Vani always secretly yearned for a career in film playback singing. After her marriage to Jairam she settled in Bombay, a city where she also saw her dream come true.

In 1970, she realized her childhood ambition of becoming a film playback singer when the veteran hindi film music director, Vasant Desai chose her voice for the hindi feature film Guddi. She recorded three songs for that film. Bol Re Papi Hara, her song from the film, based on the hindustani raga Miyan Malhar, instantly made her an household name in the different corners of India. The song was awarded Tansen Samman (for best classical-based song in a hindi film,) The Lions International Best Promising Singer, The All India Cinegoers Association, and the All India Film-goers Association awards for the Best Playback Singer in 1971. Vani recorded her first tamil song for the tamil film Thaiyum Seiyum, for S.M.Subbaiah Naidu, in the year 1973.

Besides Hindi and Tamil, Vani Jairam has numerous recordings in other languages of India. These include, Gujarati, Marathi, Marwari, Hariyanvi, Malayalam, Kannada, Telugu, Oriya, Bengali and Tulu. For her work in these languages she has been awarded many prestigious awards, among which are: Best Female Playback Singer for states of Gujarat (1975), Tamil Nadu (1980) and Orissa (1984).

Vani Jairam was chosen for the Indian President's National Award for Best Female Playback Singer of 1975, for her work in M.S. Viswanathan's Aboorva Ragangal (Tamil). Her songs in the Pt. Ravi Shankar scored film Meera brought her the Film World (1979) Cine Herald (1979) and Filmfare (1980) awards for Best Playback Singer in Hindi. Shankarabharanam (Telugu), the film scored by K.V. Mahadevan, gave Vani Jairam her second National Award as Best Playback Singer of 1980. Once again, she was awarded her third National Award for Best Playback Singer of 1991 for K.V. Mahadevan's Swati Kiranam. She is also the youngest artiste to be awarded the Sangeet Peet Samman.

Vani Jairam studied Carnatic music under the tutelage of Kadalur Srinivasa Iyengar, T.R. Balasubramanian and R.S. Mani. Her Hindustani light-classical music guru was Ustad Abdul Rahman Khan.