// remove non-alphanumerics function innocent(a) { var b=''; for (var i=0; i='A' && c<='Z') || (c>='a' && c<='z') || (c>='0' && c<='9') || c=='_') { b+=c; } } return b; } // 100: 276m // 1000: 289m // 10000: 446m function looper() { for (var i=0; i<3500; ++i) { // 797m (52 chars, no matter which chars) var n = innocent('xxxxxxx..xxxx//////////xxxxxxxxxxxxxxxxxxxxxxxxxxxxx'+i); } } looper();