I have strings like, $a = 'helloMister'; $b = 'doggyWaltz'; $c = 'bumWipe'; $d = 'pinkNips'; How can I explode at the capital letters, search on google for some time and came back with nothing! Thanks. 解决: If you want to split helloMister into hello and Mister you can use preg_split to split the string at a point just before the uppercase letter