Quick & Easy CSS Compression Using PHP

Discussion

1. Jesus D

   What about the performance of this script?
   I can imagine the concatenating the $css can get quite expensive. Maybe add some caching mechanism that wont have to reread the files and perform that nasty string replace.

   Just a suggestion. :)
2. david

   Thank you for contributing Jesus.

   It all depends on how frequently you update your CSS.

   You could definitely save the output of this script and simply reference that.

   David
3. James

   Cool script. Depending on the size of the site, I find it most efficient to incorporate the CSS packing during the build process, and release as a static CSS file. Then configure Apache to gzip output of CSS files to shrink even further ;)
4. Andreas

   Nice! Just what I was looking for.
5. Christine Furst

   What a pitty. My webserver ( one.com ) does not seem to support this usage of the .htaccess file. :-(
   Cheers, Stinie
6. Thomas Wilhelm

   I added some code and I think it improved the compression a little bit:

   $css = str_replace(': ', ':', str_replace(';}', '}', str_replace('; ',';',str_replace(' }','}',str_replace(' {', '{', str_replace('{ ','{',str_replace(array("\r\n","\r","\n","\t",'  ','    ','    '),"",preg_replace('!/\*[^*]*\*+([^/][^*]*\*+)*/!','',$css))))))));
7. tutoriale pc

   I’ve used this script on my website. Thanks!
8. M1ke

   Thanks, this code (and the idea behind it) was very useful. I had to change how it was output as originally the browser wouldn’t read it – could have been due to server settings. I just added this to the end:
   header("Content-type: text/css");
echo $css
   Also the code Thomas Whilhelm posted was useful, it did shave an extra kB off the document but only after I removed the 5-7th elements of the 7th str_replace:
   $css=str_replace(': ', ':', str_replace(';}', '}', str_replace('; ',';',str_replace(' }','}',str_replace(' {', '{', str_replace('{ ','{',str_replace(array("\r\n","\r","\n","\t"),"",preg_replace('!/\*[^*]*\*+([^/][^*]*\*+)*/!','',$css))))))));
   With those extra elements (which came out as spaces on here) it messes up any nested CSS (i.e. most of it)
9. CJ

   I simplified it even further and cut out as much whitespace as possible with this code. I’ve rearranged the spaghetti into a function just because I prefer it that way. Feel free to re-spaghetti.

   
function compress($css){
// Remove comments
$css = preg_replace('!/\*[^*]*\*+([^/][^*]*\*+)*/!', '', $css);
// Remove spaces before and after symbols
$css = preg_replace('/(\s(?=\W))|((?<=\W)\s)/', '', $css);
// Remove remaining whitespace
$css = str_replace(array("\r\n","\r","\n","\t",' ',' ',' '), '', $css);
return $css;
}

• Yotam

  @CJ
  This compression code is great, one issue though.

  I used your code to compress and it incorrectly removes spaces after classes.

  This

  .alert .title { font-size: 15px; }

  Comes out as:

  .alert.title{font-size:15px;}
10. Lyricstub

    Extremely simple to implement, I tried code.google.com/p/minify/ but it is very hard to adopt and implement.
    Your code is so simple and light weight to implement.
    It will be implemented in next release of my product.

    It would be appreciated if you can help me understand: what is difference between css.css to be treated as PHP rather than url rewriting?

    Cheers!!!
11. JmsRie

    Super helpful..
    need also to add this bit of code in order to work maybe due to some server settings like M1ke did. Thanks a lot!!
    
header("Content-type: text/css");

12. Roman

    Thanks for codes,…

    but i created my own compressor.
    http://www.igloro.info/en/css_compressor.html
13. huh...

    Nicely done.

    Hey roman, if yours is different … why aren’t you showing your work? :D
14. Myroslav

    Hi!
    There is php extension which can compress js and css files

    https://github.com/kufd/jsCssCompressor
15. Jonas Røssum

    Thanks so much for this! I don’t know if I overlooked something, but what about spaces before “{” and after “:”?

    http://pastebin.com/LqzkuJqP
16. Gerben van Dijk

    Thanks, just what I needed. I used it to compress the result from the LESSCSS PHP processor like this:

    compileFile($input);
      
      echo str_replace('; ',';',str_replace(' }','}',str_replace('{ ','{',str_replace(array("\r\n","\r","\n","\t",'  ','    ','    '),"",preg_replace('!/\*[^*]*\*+([^/][^*]*\*+)*/!','',$css)))));  
    
    } catch (exception $e) {
    
      echo "fatal error: " . $e->getMessage();
      
    }
    
17. Gerben van Dijk

    David, something is going wrong with the comments.. i tried to use a PRE tag or a GIST embed, but anyway, here is the link: https://gist.github.com/gport/5116023
18. rakesh kumar

    your code is not working properly. The only option left with me is using google pagespeed service to get my css properly minified. Though your code minify css but also remove some vital information that affect our css very badly. is there any solution for this issue. Waiting for your kind attention on this issue.
19. Taufik Nurrohman

    Another examples including HTML and JavaScript minifier in pure PHP → https://gist.github.com/tovic/d7b310dea3b33e4732c0
20. Adrian

    Hello, great code but I have suggestions too.

    Replace:
    – color like #ffffff with #fff
    – symbols like ;} with only }
    – numbers like 0px with 0 (only zero)