diff --git a/actions/avatarsettings.php b/actions/avatarsettings.php
index 68c6ce701d..0f8122c075 100644
--- a/actions/avatarsettings.php
+++ b/actions/avatarsettings.php
@@ -75,7 +75,7 @@ class AvatarsettingsAction extends AccountSettingsAction
 
     function getInstructions()
     {
-        return _('You can upload your personal avatar.');
+        return _('You can upload your personal avatar. The maximum file size is '.ImageFile::maxFileSize().'.');
     }
 
     /**
@@ -155,7 +155,7 @@ class AvatarsettingsAction extends AccountSettingsAction
         $this->element('input', array('name' => 'MAX_FILE_SIZE',
                                       'type' => 'hidden',
                                       'id' => 'MAX_FILE_SIZE',
-                                      'value' => MAX_AVATAR_SIZE));
+                                      'value' => ImageFile::maxFileSize(true)));
         $this->elementEnd('li');
         $this->elementEnd('ul');
 
diff --git a/actions/grouplogo.php b/actions/grouplogo.php
index 294005f1bb..473303373f 100644
--- a/actions/grouplogo.php
+++ b/actions/grouplogo.php
@@ -152,7 +152,7 @@ class GrouplogoAction extends Action
 
     function getInstructions()
     {
-        return _('You can upload a logo image for your group.');
+        return _('You can upload a logo image for your group. The maximum file size is '.ImageFile::maxFileSize().'.');
     }
 
     /**
@@ -229,7 +229,7 @@ class GrouplogoAction extends Action
         $this->element('input', array('name' => 'MAX_FILE_SIZE',
                                       'type' => 'hidden',
                                       'id' => 'MAX_FILE_SIZE',
-                                      'value' => MAX_AVATAR_SIZE));
+                                      'value' => ImageFile::maxFileSize(true)));
         $this->elementEnd('li');
         $this->elementEnd('ul');
 
diff --git a/lib/common.php b/lib/common.php
index 825ba0ff75..482800876d 100644
--- a/lib/common.php
+++ b/lib/common.php
@@ -24,7 +24,6 @@ define('LACONICA_VERSION', '0.7.0');
 define('AVATAR_PROFILE_SIZE', 96);
 define('AVATAR_STREAM_SIZE', 48);
 define('AVATAR_MINI_SIZE', 24);
-define('MAX_AVATAR_SIZE', 256 * 1024);
 
 define('NOTICES_PER_PAGE', 20);
 define('PROFILES_PER_PAGE', 20);
diff --git a/lib/imagefile.php b/lib/imagefile.php
index 5e9913235c..74c3d14f03 100644
--- a/lib/imagefile.php
+++ b/lib/imagefile.php
@@ -72,7 +72,7 @@ class ImageFile
             break;
         case UPLOAD_ERR_INI_SIZE:
         case UPLOAD_ERR_FORM_SIZE:
-            throw new Exception(_('That file is too big.'));
+            throw new Exception(_('That file is too big. The maximum file size is '.$this->maxFileSize().'.'));
             return;
         case UPLOAD_ERR_PARTIAL:
             @unlink($_FILES[$param]['tmp_name']);
@@ -182,4 +182,32 @@ class ImageFile
     {
         @unlink($this->filename);
     }
+    
+    static function maxFileSize($return_bytes = false)
+    {
+        $limit = min(ImageFile::strToInt(ini_get('post_max_size')), ImageFile::strToInt(ini_get('upload_max_filesize')), ImageFile::strToInt(ini_get('memory_limit')));
+        
+        if ($return_bytes) {
+            return $limit;
+        }
+        
+        return ($limit/(1024*1024)).'MB';
+    }
+    
+    static function strToInt($str)
+    {
+        $unit = substr($str, -1);
+        $num = substr($str, 0, -1);
+        
+        switch(strtoupper($unit)){
+            case 'G':
+                $num *= 1024;
+            case 'M':
+                $num *= 1024;
+            case 'K':
+                $num *= 1024;
+        }
+        
+        return $num;
+    }
 }
\ No newline at end of file