diff --git a/doc/man-sections/advanced-options.rst b/doc/man-sections/advanced-options.rst
index d5a6b4f2..e1115e49 100644
--- a/doc/man-sections/advanced-options.rst
+++ b/doc/man-sections/advanced-options.rst
@@ -9,13 +9,17 @@ Standalone Debug Options
   ::
 
      --show-gateway
+     --show-gateway IPv4-target
      --show-gateway IPv6-target
 
+  For IPv4 it looks for a 0.0.0.0/0 route, or the specified IPv4 address
+  if the target can be parsed as an IPv4 address.
   For IPv6 this queries the route towards ::/128, or the specified IPv6
-  target address if passed as argument.
-  For IPv4 on Linux, Windows, MacOS and BSD it looks for a 0.0.0.0/0 route.
-  If there are more specific routes, the result will not always be matching
-  the route of the IPv4 packets to the VPN gateway.
+  target address if the argument is an IPv6 address.
+
+  Adding a target is helpful for diagnostics to see if OpenVPN will do
+  the right thing if there are more specific IPv4/IPv6 routes to a
+  VPN server.
 
 
 Advanced Expert Options
diff --git a/src/openvpn/options.c b/src/openvpn/options.c
index 5a80e6b7..218d8a66 100644
--- a/src/openvpn/options.c
+++ b/src/openvpn/options.c
@@ -788,7 +788,7 @@ static const char usage_message[] =
     "\n"
     "General Standalone Options:\n"
 #ifdef ENABLE_DEBUG
-    "--show-gateway : Show info about default gateway.\n"
+    "--show-gateway [address]: Show info about gateway [to v4/v6 address].\n"
 #endif
 ;
 
@@ -5858,20 +5858,26 @@ add_option(struct options *options,
     {
         struct route_gateway_info rgi;
         struct route_ipv6_gateway_info rgi6;
-        struct in6_addr remote = IN6ADDR_ANY_INIT;
+        in_addr_t remote_ipv4 = 0;
+        struct in6_addr remote_ipv6 = IN6ADDR_ANY_INIT;
         openvpn_net_ctx_t net_ctx;
         VERIFY_PERMISSION(OPT_P_GENERAL);
         if (p[1])
         {
-            get_ipv6_addr(p[1], &remote, NULL, M_WARN);
+            /* try parsing the argument as a v4 or v6 address - if
+             * possible, the output will show the exact route there, and
+             * "the default route" for the other protocol
+             */
+            remote_ipv4 = get_ip_addr(p[1], M_WARN, NULL);
+            get_ipv6_addr(p[1], &remote_ipv6, NULL, M_WARN);
         }
         net_ctx_init(NULL, &net_ctx);
-        get_default_gateway(&rgi, 0, &net_ctx);
-        get_default_gateway_ipv6(&rgi6, &remote, &net_ctx);
+        get_default_gateway(&rgi, remote_ipv4, &net_ctx);
+        get_default_gateway_ipv6(&rgi6, &remote_ipv6, &net_ctx);
         print_default_gateway(M_INFO, &rgi, &rgi6);
         openvpn_exit(OPENVPN_EXIT_STATUS_GOOD); /* exit point */
     }
-#endif
+#endif /* if defined(ENABLE_DEBUG) && !defined(ENABLE_SMALL) */
     else if (streq(p[0], "echo") || streq(p[0], "parameter"))
     {
         struct buffer string = alloc_buf_gc(OPTION_PARM_SIZE, &gc);