Wishes poured in for Tendulkar, whose birthday will be celebrated by his former Indian Premier League (IPL) franchise Mumbai Indians later.
"Happy B'day Paaji. May God bless you with more happiness and peace in life. My cricket hero always," India skipper Virat Kohli tweeted.
India coach Anil Kumble wished the Master Blaster, tweeting "#HappyBirthdaySachin. One of the most inspiring sportsmen the world has seen. Hope you have a splendid year ahead @sachin_rt."
In his congratulatory message for Tendulkar, former India opener Virender Sehwag wrote: "To a man who could stop time in India, #HappyBirthday Sachin @sachin_rt."
Off-spinner R. Ashwin quipped that April 24 could well be declared the 'Indian Cricket Day'.
"Many more happy returns of the day @sachin_rt , April 24th should be marked as Indian cricket day. I was lucky to have played along side you," he tweeted.
Kolkata Knight Riders captain Gautam Gambhir wrote: "@sachin_rt may God Almighty continue to smile on you. A very happy birthday paaji, have a blast. #HappyBirthdaySachin"
"Happy birthday paaji @sachin_rt lots of love and best wishes khush raho tandrust raho (be happy, be well)..we love you," off-spinner Harbhajan Singh wrote on his twitter handle.
"Special day, special person and special celebration. May all your dreams and desires come true. Happy birthday Sachin @sachin_rt," is what India pacer Umesh Yadav wrote in his greetings message.
"Happy B'day to a man who has touched an emotional chord with a billion people, a part of our lives forever, @sachin_rt#HappyBirthdaySachin," former India cricketer Mohammad Kaif wrote in his message.
Australia legend Adam Gilchrist also took to Twitter to wish the batting maestro.
"Happy birthday @sachin_rt and @bowlologist," tweeted Australian wicket-keeping legend Adam Gilchrist.
Former Australia skipper Michael Clarke wrote: "Happy bday to the great @sachin_rt, 44 years young today. Hope you have a great day and year to come mate!"
Promising batsman Rishabh Pant also wished Tendulkar on his birthday.
"Happy Birthday @sachin_rt sir. May keep inspiring millions like us for years to come," he tweeted.
Indian boxing star Vijender Singh also took to social media to wish the batting great on his 44th birthday.
"Happy birthday God of cricket & BharatRatna @sachin_rt sir ????#HappyBirthdaySachin," tweeted Vijender.
West Bengal chief minister Mamata Banerjee tweeted: "Happy Birthday @sachin_rt Wishing you and your family all the happiness"
Tendulkar amassed 34,357 runs in his 24-year career.
In ODIs, he has scored 18,426 while in Tests he has 15,921 runs to his credit.
After his retirement in 2013, Tendulkar received the Bharat Ratna award and became a Rajya Sabha member. He also played in the Indian Premier League but stopped after the sixth season.