Retrieve WordPress root directory path?

How can I retrieve the path to the root directory in WordPress CMS?

Looking at the bottom of your wp-config.php file in the wordpress root directory will let you find something like this:

if ( !defined('ABSPATH') )
    define('ABSPATH', dirname(__FILE__) . '/');

For an example file have a look here:
http://core.trac.wordpress.org/browser/trunk/wp-config-sample.php

You can make use of this constant called ABSPATH in other places of your wordpress scripts and in most cases it should point to your wordpress root directory.

echo ABSPATH; // This shows the absolute path of WordPress

ABSPATH is a constant defined in the wp-config.php file.

Note: This answer is really old and things may have changed in WordPress land since.

I am guessing that you need to detect the WordPress root from your plugin or theme. I use the following code in FireStats to detect the root WordPress directory where FireStats is installed a a WordPress plugin.

function fs_get_wp_config_path()
{
    $base = dirname(__FILE__);
    $path = false;

    if (@file_exists(dirname(dirname($base))."/wp-config.php"))
    {
        $path = dirname(dirname($base))."/wp-config.php";
    }
    else
    if (@file_exists(dirname(dirname(dirname($base)))."/wp-config.php"))
    {
        $path = dirname(dirname(dirname($base)))."/wp-config.php";
    }
    else
        $path = false;

    if ($path != false)
    {
        $path = str_replace("\\", "/", $path);
    }
    return $path;
}

There are 2 answers for this question Url & directory. Either way, the elegant way would be to define two constants for later use.

define (ROOT_URL, get_site_url() );
define (ROOT_DIR, get_theme_root() );

This an old question, but I have a new answer. This single line will return the path inside a template: :)

$wp_root_path = str_replace('/wp-content/themes', '', get_theme_root());

   Please try this for get the url of root file.

First Way:

 $path = get_home_path();
   print "Path: ".$path; 
// Return "Path: /var/www/htdocs/" or

// "Path: /var/www/htdocs/wordpress/" if it is subfolder

Second Way:

And you can also use 

    "ABSPATH"

this constant is define in wordpress config file.

theme root directory path code

 <?php $root_path = get_home_path(); ?> 
print "Path: ".$root_path;

Return "Path: /var/www/htdocs/" or "Path: /var/www/htdocs/wordpress/" if it is subfolder

Theme Root Path

 $theme_root = get_theme_root();
 echo $theme_root

Results:- /home/user/public_html/wp-content/themes

For retrieving the path you can use a function <?php $path = get_home_path(); ?>. I do not want to just repeat what had been already said here, but I want to add one more thing:

If you are using windows server, which is rare case for WordPress installation, but still happens sometimes, you might face a problem with the path output. It might miss a "\" somewhere and you will get an error if you will be using such a path. So when outputting make sure to sanitize the path:

<?php 

$path = get_home_path(); 
$path = wp_normalize_path ($path);

// now $path is ready to be used :)

?>

I think this would do the trick:

function get_wp_installation()
{
    $full_path = getcwd();
    $ar = explode("wp-", $full_path);
    return $ar[0];
}

I like @Omry Yadan's solution but I think it can be improved upon to use a loop in case you want to continue traversing up the directory tree until you find where wp-config.php actually lives. Of course, if you don't find it and end up in the server's root then all is lost and we return a sane value (false).

function wp_get_web_root() {

  $base = dirname(__FILE__);
  $path = false;

  while(!$path && '/' != $base) {
    if(@file_exists(dirname($base)).'/wp-config.php') {
      $path = dirname($base);
    } else {
      $base = dirname($base);
    }
  }

  return $path;
}

Here are the various WorPress solutions get the directory. You can pick anyone as per the need.

 echo "<br/>".get_home_url();     // https://mysiteurl.com

 echo "<br/>".ABSPATH;            // /app/

 echo "<br/>".get_home_path();    // /app/

 echo "<br/>".get_site_url();     // https://mysiteurl.com

 echo "<br/>".get_template_directory(); // /app/wp-content/themes/mytheme

 echo "<br/>".dirname(__FILE__);  // /app/wp-content/plugins/myplugin/includes

 echo "<br/>".get_theme_root();   // /app/wp-content/themes

 echo "<br/>".plugin_dir_path( __FILE__ ); // /app/wp-content/plugins/myplugin/includes/

 echo "<br/>".getcwd();           // /app/wp-admin

If you have WordPress bootstrap loaded you can use get_home_path() function to get path to the WordPress root directory.

I like the accepted answer and @cfx's solution, but they can be consolidated a bit more:

function base_dir () {
    $path = dirname(__FILE__);
    while (true) {
        if (file_exists($path."/wp-config.php")) {
            return $path."/";
        }
        $path = dirname($path);
    }
}

This allows for you to find the base directory in files that are not loaded by WordPress, such as dynamically-created javascript and css files.

Why was this made so complicated? One command:

Nginx

grep -i 'root' /etc/nginx/sites-enabled/*

Apache

grep -i 'DocumentRoot' /etc/apache2/sites-enabled/*

You can use get_site_url() function to get the base url of the wordpress site.

For more information, please visit http://codex.wordpress.org/Function_Reference/get_site_url

Try this function for get root directory path:

get_template_directory_uri();