diff --git a/avatar/__init__.py b/avatar/__init__.py
index f90f0a7..3750a07 100644
--- a/avatar/__init__.py
+++ b/avatar/__init__.py
@@ -15,6 +15,7 @@ AVATAR_GRAVATAR_DEFAULT = getattr(settings, 'AVATAR_GRAVATAR_DEFAULT', None)
 AVATAR_DEFAULT_URL = getattr(settings, 'AVATAR_DEFAULT_URL', 
     settings.MEDIA_URL + os.path.join(os.path.dirname(__file__), 'default.jpg'))
 AVATAR_MAX_AVATARS_PER_USER = getattr(settings, 'AVATAR_MAX_AVATARS_PER_USER', 42)
+AVATAR_MAX_SIZE = getattr(settings, 'AVATAR_MAX_SIZE', 1024 * 1024)
 
 from django.db.models import signals
 from django.contrib.auth.models import User
diff --git a/avatar/forms.py b/avatar/forms.py
index 6fa2ad4..471eea3 100644
--- a/avatar/forms.py
+++ b/avatar/forms.py
@@ -3,7 +3,9 @@ from django.forms import widgets
 from django.utils.safestring import mark_safe
 
 from avatar.models import Avatar
-from avatar import AVATAR_MAX_AVATARS_PER_USER
+from avatar import AVATAR_MAX_AVATARS_PER_USER, AVATAR_MAX_SIZE
+
+from django.template.defaultfilters import filesizeformat
 
 def avatar_img(avatar, size):
     if not avatar.thumbnail_exists(size):
@@ -21,6 +23,10 @@ class UploadAvatarForm(forms.Form):
         
     def clean_avatar(self):
         data = self.cleaned_data['avatar']
+        if data.size > AVATAR_MAX_SIZE:
+            raise forms.ValidationError(
+                "Your file is too big (%s), the maximum allowed size is %s" %
+                (filesizeformat(data.size), filesizeformat(AVATAR_MAX_SIZE)))
         count = Avatar.objects.filter(user=self.user).count()
         if AVATAR_MAX_AVATARS_PER_USER > 1 and \
            count >= AVATAR_MAX_AVATARS_PER_USER: