diff --git a/django/views/static.py b/django/views/static.py
index 2ff22ce13f..7dd44c5772 100644
--- a/django/views/static.py
+++ b/django/views/static.py
@@ -138,7 +138,7 @@ def was_modified_since(header=None, mtime=0, size=0):
         header_len = matches.group(3)
         if header_len and int(header_len) != size:
             raise ValueError
-        if mtime > header_mtime:
+        if int(mtime) > header_mtime:
             raise ValueError
     except (AttributeError, ValueError, OverflowError):
         return True
diff --git a/tests/regressiontests/views/tests/__init__.py b/tests/regressiontests/views/tests/__init__.py
index 63db5da2a3..12d0c59014 100644
--- a/tests/regressiontests/views/tests/__init__.py
+++ b/tests/regressiontests/views/tests/__init__.py
@@ -7,4 +7,4 @@ from .defaults import DefaultsTests
 from .i18n import JsI18NTests, I18NTests, JsI18NTestsMultiPackage
 from .shortcuts import ShortcutTests
 from .specials import URLHandling
-from .static import StaticHelperTest, StaticTests
+from .static import StaticHelperTest, StaticUtilsTests, StaticTests
diff --git a/tests/regressiontests/views/tests/static.py b/tests/regressiontests/views/tests/static.py
index 9d87ade137..38cf38ce46 100644
--- a/tests/regressiontests/views/tests/static.py
+++ b/tests/regressiontests/views/tests/static.py
@@ -2,11 +2,14 @@ from __future__ import absolute_import
 
 import mimetypes
 from os import path
+import unittest
 
 from django.conf import settings
 from django.conf.urls.static import static
-from django.test import TestCase
 from django.http import HttpResponseNotModified
+from django.test import TestCase
+from django.utils.http import http_date
+from django.views.static import was_modified_since
 
 from .. import urls
 from ..urls import media_dir
@@ -105,3 +108,14 @@ class StaticHelperTest(StaticTests):
     def tearDown(self):
         super(StaticHelperTest, self).tearDown()
         urls.urlpatterns = self._old_views_urlpatterns
+
+
+class StaticUtilsTests(unittest.TestCase):
+    def test_was_modified_since_fp(self):
+        """
+        Test that a floating point mtime does not disturb was_modified_since.
+        (#18675)
+        """
+        mtime = 1343416141.107817
+        header = http_date(mtime)
+        self.assertFalse(was_modified_since(header, mtime))