Tom Cruise is ''more relaxed'' since splitting from Katie Holmes.

The 'Oblivion' star, who celebrated his 51st birthday on Wednesday (03.07.13), has made some deliberate changes to his life since the 34-year-old actress filed for divorce from him last summer, after six years of marriage, and secured sole custody of their daughter Suri, seven.

A source close to the actor told UsMagazine.com: ''Tom has definitely made some changes to his life over the past year since the divorce.

''He's actually a lot more relaxed and more extroverted.''

The source said that Tom is currently enjoying being single and isn't ready to find a serious girlfriend, explaining: ''Now that he's single he wants to get out there a bit. He's dated a few girls, but very casually.''

A second insider said the actor, who was previously married to Nicole Kidman and Mimi Rogers, has been trying to lead a more low key life since the end of his third marriage.

The source said: ''Since the divorce, he's spent some time reflecting and actually letting go.''