"Age doesn't scare me at all. I love being 45 it is a great age," Saif told PTI.
The actor said he is going to have a quiet birthday with his family.
"I don't have specific plans for my birthday. I will celebrate it with my children...Wife... My family," he said.
Saif, who will be next seen in Kabir Khan's action thriller "Phantom", stressed on the importance of leading a healthy and responsible lifestyle.
"It is important to lead healthy life. It is also important for one to be a responsible person," the actor said.
He is the recipient of several awards, including a National Film Award. He was honoured by the Government of India with the Padma Shri in 2010.
Saif was earlier married to actress Amrita Singh for thirteen years; they have two children together. He tied the knot with actress Kareena Kapoor in 2012.