diff --git a/neutron/tests/tempest/api/test_network_ip_availability.py b/neutron/tests/tempest/api/test_network_ip_availability.py
index f84e14e..74395ea 100644
--- a/neutron/tests/tempest/api/test_network_ip_availability.py
+++ b/neutron/tests/tempest/api/test_network_ip_availability.py
@@ -99,9 +99,11 @@
 def calc_total_ips(prefix, ip_version):
     # will calculate total ips after removing reserved.
     if ip_version == lib_constants.IP_VERSION_4:
-        total_ips = 2 ** (32 - prefix) - DEFAULT_IP4_RESERVED
+        total_ips = 2 ** (lib_constants.IPv4_BITS
+                          - prefix) - DEFAULT_IP4_RESERVED
     elif ip_version == lib_constants.IP_VERSION_6:
-        total_ips = 2 ** (128 - prefix) - DEFAULT_IP6_RESERVED
+        total_ips = 2 ** (lib_constants.IPv6_BITS
+                          - prefix) - DEFAULT_IP6_RESERVED
     return total_ips