# Need help with expression
**URL:** https://community.mp3tag.de/t/need-help-with-expression/825
**Category:** Support
**Created:** [February 17, 2004, 6:44pm UTC](https://community.mp3tag.de/t/need-help-with-expression/825 "2004-02-17T18:44:07Z")
**Posts on this page:** 3
**Page:** 1
### Author:  [@dekan54](https://community.mp3tag.de/u/dekan54)
#### Post date: [February 17, 2004, 6:44pm UTC](https://community.mp3tag.de/t/need-help-with-expression/825/1 "2004-02-17T18:44:07Z")
I am not very good with building expressions so maybe someone here could help me. I have the following file name....
950 Elvis Presley - Hound Dog.mp3
How do I strip off the "950 " (a space is after the 950)
Also none of the mp3 files have any tag information in them. Can I place the artist and title in the tag somehow from the file name?
I have about 400 songs in this format and would like to do a batch process to convert them all.
Thanks
Dekan
---
### Author:  [@dano](https://community.mp3tag.de/u/dano)
#### Post date: [February 17, 2004, 7:26pm UTC](https://community.mp3tag.de/t/need-help-with-expression/825/2 "2004-02-17T19:26:25Z")
use
^\d+\s{1}
as expression on the \_FILENAME field, leave the replacement field empty
explained:
^means at the beginning of the string, \d+ means one or more numbers and \s{1} means exatly one space
and after that u can use filename-tag converter to put the info in the tag %artist% - %title% in ur case
---
### Author:  [@system](https://community.mp3tag.de/u/system)
#### Post date: [February 9, 2026, 12:19pm UTC](https://community.mp3tag.de/t/need-help-with-expression/825/3 "2026-02-09T12:19:11Z")