The musician pledged to make the world a beautiful place on his birthday.
"To my dearest friends, fans, family and well-wishers... Thank you for your kind birthday wishes, prayers and affection. You inspire me to work harder and make even more beautiful music. Luckily, I am not yet 50.
"May the Almighty keep us all united, keep our hearts pure and compassionate. Let us make the world a beautiful place with connected wisdom, love and care," Rahman posted on his Facebook page.
Starting his career by composing ad jingles, Rahman was approached by Mani Ratnam to compose the score and soundtrack for his Tamil film "Roja".
More From This Section
The music of the film became a hit, giving Rahman a Best Music Director trophy at the National Film Awards. Rahman's first big break in Hindi film came with Ram Gopal Varma's "Rangeela".
(Reopens DES 9)
Celebrities from Indian film industry like melody queen Lata Mangeshkar, filmmaker Karan Johar and actor Anil Kapoor took to Twitter to wish the musical genius on his 49th birthday.
Johar also wished him, "To the man who changed the sound of music .....Happy birthday! arrahman."
Anil, who starred in Rahman's Oscar-winning film "Slumdog Millionaire" wished him success.
"Happy Birthday @arrahman! May your vision for #KMMC take Indian music to greater heights," he wrote.
Anil's actress daughter Sonam Kapoor also tweeted, "Happy birthday to the man who gave soul to two of my films !! @arrahman I'm your biggest fan!."
Saluting the world acclaimed composer, popular Bengali actor Prosenjit Chatterjee wrote, "Saluting the musical maestro @arrahman on his birthday. Thanks for gifting us so many wonderful tunes and eagerly waiting for more and more."