I have a string like this: 33 00 4b 46 ff ff 03 10 30 t=25562 I am only interested in the five digits at the very end after the t= How can I get this numbers with a regular expression out of it? I tried grep t=..... but I also got all characters including the t= in the beginning, which I would like to drop? After finding that five digit number, I would like to divide this by 1000. So in the above mentioned case the number 25.562. Is this possible with grep and regular expressions? Thanks for your help.