diff --git a/roles/dhcpd/templates/dhcpd.conf.j2 b/roles/dhcpd/templates/dhcpd.conf.j2
index 2b10c6a..298569c 100644
--- a/roles/dhcpd/templates/dhcpd.conf.j2
+++ b/roles/dhcpd/templates/dhcpd.conf.j2
@@ -24,7 +24,7 @@ log-facility local7;
 # Freifunk Regensburg
 subnet {{ batman_ipv4 | ipaddr('network') }} netmask {{ batman_ipv4 | ipaddr('netmask') }} {
   option routers {{ batman_ipv4 | ipaddr('address') }};
-  option interface-mtu {{ mtu }};
+  option interface-mtu {{ (mtu | int) - 32 }};
   pool {
     range {{ dhcpd_first }} {{ dhcpd_last }} ;
   }