diff --git a/unittest/commands/test_groups.cpp b/unittest/commands/test_groups.cpp
index 0c8a7cd83c..52b93fe742 100644
--- a/unittest/commands/test_groups.cpp
+++ b/unittest/commands/test_groups.cpp
@@ -246,7 +246,7 @@ TEST_F(GroupTest, Molecular)
     ASSERT_DOUBLE_EQ(group->mass(group->find("half")), 40);
     ASSERT_DOUBLE_EQ(group->mass(group->find("half"), domain->find_region("top")), 10);
     ASSERT_NEAR(group->charge(group->find("top")), 0, 1.0e-14);
-    ASSERT_DOUBLE_EQ(group->charge(group->find("right"), domain->find_region("top")), 0);
+    ASSERT_NEAR(group->charge(group->find("right"), domain->find_region("top")), 0, 1.0e-14);
 
     TEST_FAILURE(".*ERROR: Illegal group command.*", command("group three include xxx"););
 }