diff --git a/ox/net.py b/ox/net.py
index 0af61a8..5a5557a 100644
--- a/ox/net.py
+++ b/ox/net.py
@@ -71,7 +71,7 @@ def read_url(url, data=None, headers=DEFAULT_HEADERS, return_headers=False, unic
 
 def detect_encoding(data):
     if 'content="text/html; charset=utf-8"' in data or \
-        'meta charset="utf-8"' in data:
+        'meta charset="utf-8"' in data.lower():
         return 'utf-8'
     elif 'content="text/html; charset=iso-8859-1"' in data:
         return 'iso-8859-1'