diff --git a/src/libguac/guacamole/wol-constants.h b/src/libguac/guacamole/wol-constants.h
index 358d26b0..48e470c3 100644
--- a/src/libguac/guacamole/wol-constants.h
+++ b/src/libguac/guacamole/wol-constants.h
@@ -40,5 +40,12 @@
  */
 #define GUAC_WOL_DEFAULT_WAIT_TIME 60
 
+/**
+ * The size of the magic Wake-on-LAN packet to send to wake a remote host.  This
+ * consists of 6 bytes of 0xFF, and then the MAC address repeated 16 times.
+ * https://en.wikipedia.org/wiki/Wake-on-LAN#Magic_packet
+ */
+#define GUAC_WOL_PACKET_SIZE 102
+
 #endif /* GUAC_WOL_CONSTANTS_H */
 
diff --git a/src/libguac/wol.c b/src/libguac/wol.c
index c2b76660..2bf706a1 100644
--- a/src/libguac/wol.c
+++ b/src/libguac/wol.c
@@ -99,7 +99,7 @@ static ssize_t __guac_wol_send_packet(const char* broadcast_addr,
 
 int guac_wol_wake(const char* mac_addr, const char* broadcast_addr) {
     
-    unsigned char wol_packet[102];
+    unsigned char wol_packet[GUAC_WOL_PACKET_SIZE];
     unsigned int dest_mac[6];
     
     /* Parse mac address and return with error if parsing fails. */