diff --git a/chalice/app.py b/chalice/app.py
index 48b257713..bdb36c895 100644
--- a/chalice/app.py
+++ b/chalice/app.py
@@ -345,7 +345,8 @@ def __init__(self, body, headers=None, status_code=200):
     def to_dict(self, binary_types=None):
         body = self.body
         if not isinstance(body, _ANY_STRING):
-            body = json.dumps(body, default=handle_decimals)
+            body = json.dumps(body, separators=(',', ':'),
+                              default=handle_decimals)
         response = {
             'headers': self.headers,
             'statusCode': self.status_code,
diff --git a/tests/functional/test_local.py b/tests/functional/test_local.py
index 78cb70f7e..f2a5ade0b 100644
--- a/tests/functional/test_local.py
+++ b/tests/functional/test_local.py
@@ -156,7 +156,7 @@ def test_can_accept_get_request(config, sample_app, local_server_factory):
     local_server, port = local_server_factory(sample_app, config)
     response = local_server.make_call(requests.get, '/', port)
     assert response.status_code == 200
-    assert response.text == '{"hello": "world"}'
+    assert response.text == '{"hello":"world"}'
 
 
 def test_can_get_unicode_string_content_length(
@@ -222,7 +222,7 @@ def test_can_accept_multiple_connections(config, sample_app,
             'from going though.'
         )
     assert response.status_code == 200
-    assert response.text == '{"hello": "world"}'
+    assert response.text == '{"hello":"world"}'
 
 
 def test_can_import_env_vars(unused_tcp_port, http_session):
diff --git a/tests/unit/test_app.py b/tests/unit/test_app.py
index afec1ed13..01500006b 100644
--- a/tests/unit/test_app.py
+++ b/tests/unit/test_app.py
@@ -171,7 +171,7 @@ def test_can_encode_binary_json(sample_app):
         headers={'Content-Type': 'application/json'}
     )
     encoded_response = response.to_dict(sample_app.api.binary_types)
-    assert encoded_response['body'] == 'eyJmb28iOiAiYmFyIn0='
+    assert encoded_response['body'] == 'eyJmb28iOiJiYXIifQ=='
 
 
 def test_can_parse_route_view_args():
@@ -510,7 +510,7 @@ def index_view():
 
     event = create_event('/index', 'GET', {})
     response = demo(event, context=None)
-    assert response == {'statusCode': 200, 'body': '{"foo": "bar"}',
+    assert response == {'statusCode': 200, 'body': '{"foo":"bar"}',
                         'headers': {'Content-Type': 'application/json'}}