diff --git a/compose/utils.py b/compose/utils.py
index d441a2dae..76a4c6b93 100644
--- a/compose/utils.py
+++ b/compose/utils.py
@@ -3,7 +3,7 @@ import hashlib
 
 
 def json_hash(obj):
-    dump = json.dumps(obj, sort_keys=True)
+    dump = json.dumps(obj, sort_keys=True, separators=(',', ':'))
     h = hashlib.sha256()
     h.update(dump)
     return h.hexdigest()