diff --git a/matchcode/api.py b/matchcode/api.py
index 6294fb09..68844b8d 100644
--- a/matchcode/api.py
+++ b/matchcode/api.py
@@ -15,6 +15,7 @@
 from rest_framework.decorators import action
 from rest_framework.response import Response
 from rest_framework.serializers import CharField
+from rest_framework.serializers import FloatField
 from rest_framework.serializers import HyperlinkedRelatedField
 from rest_framework.serializers import ModelSerializer
 from rest_framework.serializers import ReadOnlyField
@@ -92,7 +93,7 @@ class BaseDirectoryIndexMatchSerializer(Serializer):
         lookup_field='uuid',
         read_only=True
     )
-    similarity_score = CharField()
+    similarity_score = FloatField()
 
 
 class CharMultipleWidget(widgets.TextInput):
diff --git a/matchcode/tests/test_api.py b/matchcode/tests/test_api.py
index 93c29ca3..8decc568 100644
--- a/matchcode/tests/test_api.py
+++ b/matchcode/tests/test_api.py
@@ -117,7 +117,7 @@ def test_api_approximate_directory_content_index_match_close_match(self):
         self.assertEqual(expected_matched_fingerprint, result['matched_fingerprint'])
         expected_package = 'http://testserver' + reverse('api:package-detail', args=[self.test_package1.uuid])
         self.assertEqual(expected_package, result['package'])
-        self.assertEqual('0.9453125', result['similarity_score'])
+        self.assertEqual(0.9453125, result['similarity_score'])
 
     def test_api_approximate_directory_structure_index_match_close_match(self):
         # This test fingerprint has a hamming distance of 7 from the expected fingerprint
@@ -134,7 +134,7 @@ def test_api_approximate_directory_structure_index_match_close_match(self):
         self.assertEqual(expected_matched_fingerprint, result['matched_fingerprint'])
         expected_package = 'http://testserver' + reverse('api:package-detail', args=[self.test_package2.uuid])
         self.assertEqual(expected_package, result['package'])
-        self.assertEqual('0.9453125', result['similarity_score'])
+        self.assertEqual(0.9453125, result['similarity_score'])
 
     def test_api_approximate_directory_content_index_match(self):
         test_fingerprint = '00000007af7d63765c78fa516b5353f5ffa7df45'
@@ -149,7 +149,7 @@ def test_api_approximate_directory_content_index_match(self):
         self.assertEqual(test_fingerprint, result['matched_fingerprint'])
         expected_package = 'http://testserver' + reverse('api:package-detail', args=[self.test_package1.uuid])
         self.assertEqual(expected_package, result['package'])
-        self.assertEqual('1.0', result['similarity_score'])
+        self.assertEqual(1.0, result['similarity_score'])
 
     def test_api_approximate_directory_structure_index_match(self):
         test_fingerprint = '00000004d10982208810240820080a6a3e852486'
@@ -164,4 +164,4 @@ def test_api_approximate_directory_structure_index_match(self):
         self.assertEqual(test_fingerprint, result['matched_fingerprint'])
         expected_package = 'http://testserver' + reverse('api:package-detail', args=[self.test_package2.uuid])
         self.assertEqual(expected_package, result['package'])
-        self.assertEqual('1.0', result['similarity_score'])
+        self.assertEqual(1.0, result['similarity_score'])