diff --git a/pywwt/jupyter_server.py b/pywwt/jupyter_server.py
index 3722f9c7..49619e93 100644
--- a/pywwt/jupyter_server.py
+++ b/pywwt/jupyter_server.py
@@ -1,5 +1,6 @@
 import os
 import json
+import mimetypes
 from hashlib import md5
 from tornado import web
 from notebook.utils import url_path_join
@@ -33,6 +34,9 @@ def get(self, filename):
             else:
                 raise web.HTTPError(404)
 
+        # Do our best to set an appropriate Content-Type.
+        self.set_header('Content-Type', mimetypes.guess_type(filename)[0])
+
         with open(path, 'rb') as f:
             content = f.read()