Here is what they have tweeted:
Taapsee Pannu: Everytime I feel tired or feel something is impossible I look up to him and charge through a brick wall Happy birthday Akshay kumar.
Suniel Shetty: A big thumbs up to the way you are steering your journey Akki, adding life to days and not days to life! A very very happy birthday Akshay Kumar.
Ritesh Sidhwani: Happy birthday Akshay Kumar have a super year. Stay blessed and happy. Sending you loads of happiness and love from LA. Akshay turns 'Gold'.
Sajid Khan: 50! Unreal sundi! Wishing the planet's fittest half centurion a very happy birthday. Love you. Happy birthday Akshay kumar.
Raj Kundra: Happy birthday to my fellow Virgo and praaji Akshay Kumar.
Milap Zaveri: Happy birthday Akshay Kumar sir! You are an inspiration and your dedication is something we all should learn from! Have a great day and year!
Maniesh Paul: Happy birthday Akshay Kumar sir... Stay blessed... Loads of love and regards.
Akshay's career spans more than twenty five years and has over a hundred Hindi films including hits "Dhadkan", "Namastey London", "Bhool Bhulaiyaa", "Hera Pheri", "Mujhse Shaadi Karogi", "Garam Masala", "Bhagam Bhag", "Singh Is Kinng", "Housefull", "Rowdy Rathore", "OMG", "Special 26", "Holiday", "Gabbar Is Back", "Airlift", "Rustom", "Jolly LLB 2" and "Toilet: Ek Prem Katha".
He began his acting career in the 1990s and primarily starred in action films and was known for his appearances in films of the "Khiladi" series. Later, he also gained fame for his drama, romantic, comic roles and socially relevant movies.
In 2008, he hosted the show "Fear Factor - Khatron Ke Khiladi". The next year, he founded the Hari Om Entertainment production company. In 2012, he founded another production company called Grazing Goat Pictures. In 2014, Kumar launched TV reality show "Dare 2 Dance".
In 2015, he was ranked 9th in Forbes' first global list of highest paid actors in the world.