diff --git a/tests/test_network_tools.py b/tests/test_network_tools.py
new file mode 100644
index 0000000000000000000000000000000000000000..2f3b9744f950e7f7190d2fa6d9bd0d098b0aa2ff
--- /dev/null
+++ b/tests/test_network_tools.py
@@ -0,0 +1,33 @@
+"""
+Copyright  2016-2021 Maël Azimi <m.a@moul.re>
+
+Silkaj is free software: you can redistribute it and/or modify
+it under the terms of the GNU Affero General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+Silkaj is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU Affero General Public License for more details.
+
+You should have received a copy of the GNU Affero General Public License
+along with Silkaj. If not, see <https://www.gnu.org/licenses/>.
+"""
+
+import pytest
+from silkaj import network_tools
+
+
+@pytest.mark.parametrize(
+    "address,type",
+    [
+        ("test.domain.com", 0),
+        ("8.8.8.8", 4),
+        ("2001:0db8:85a3:0000:0000:8a2e:0370:7334", 6),
+        ("2001:db8::1:0", 6),
+        ("2001:0db8:0t00:0000:0000:ff00:0042:8329", 0),
+    ],
+)
+def test_check_ip(address, type):
+    assert network_tools.check_ip(address) == type