diff --git a/src/probe_modules/module_udp.c b/src/probe_modules/module_udp.c
index 82c6255..3f78819 100644
--- a/src/probe_modules/module_udp.c
+++ b/src/probe_modules/module_udp.c
@@ -299,6 +299,6 @@ probe_module_t module_udp = {
 	.process_packet = &udp_process_packet,
 	.close = &udp_global_cleanup,
 	.fields = fields,
-	.numfields = 6 
+	.numfields = sizeof(fields)/sizeof(fields[0]) 
 };