Here is complete list of Prime Ministers of India. This list is sort on the basis on time period of their tenure.
(1) Pandit Jawahar Lal Nehru (15th August 1947-27th May 1964) – 16 years 9 months 13 days (Longest Tenure)
(2) Smt. Indira Gandhi (24th January 1966-24th March 1977, 14th January 1980-31st October 1984) – 15 Years, 11 Months, 19 Days
(3) Dr. Manmohan Singh (22th May 2004-26th May 2014) – 10 Years 05 Days
(4) Narendra Modi (26th May 2014 – As on 31st January 2022) – 7 Years 8 Month 5 Days (Still continue)
(5) Atal Bihari Vajpeyee (16th May 1996-01st June 1996, 19th March 1998-13th October 1999, 13th October 1999-22th May 2004) – 6 Years 2 months 19 days.
(6) Rajiv Gandhi (31st October 1984 – 02nd December 1989) – 5 Years 1 Month 2 Days
(7) P. V. Narsimha Rao (21st June 1991 – 16th May 1996) – 4 years 11 months 25 days
(8) Morarji Desai (24th May 1977 – 28th July 1979) – 2 years 4 months 4 days
(9) Lal Bahadur Shastri (09th June 1964 – 11th January 1966) – 1 years 7 months 3 days
(10) Vishwanath Pratap Singh (02nd December 1989 – 10th November 1990) – 11 months 8 days
(11) Inder Kumar Gujral (21st April 1997-19th March 1998) – 10 months 26 days
(12) H. D. Deve Gowda (01st June 1996-21st April 1997) – 10 months 20 days
(13) Chandreshekhar (10th November 1990 – 21st June 1991) – 7 months 11 days
(14) Chaudhary Charan Singh (28th July 1979 – 14th January 1980) – 5 months 17 days
(15) Gulzarilal Nanda (As Interim Prime Minister of India) (29th August 1963 – 14th November 1966, 11th January 1966 – 24th January 1966 ) – 3 month 17 days