diff --git a/sonoff/_changelog.ino b/sonoff/_changelog.ino
index ed88da8c4..e9050aafb 100644
--- a/sonoff/_changelog.ino
+++ b/sonoff/_changelog.ino
@@ -3,6 +3,7 @@
  * Redesign command Tariff to now default to 0 (=disabled) and allowing to set both Standard Time (ST) and Daylight Savings Time (DST) start hour
  *  Commands Tariff1 22,23 = Tariff1 (Off-Peak) ST,DST   Tariff2 (Standard) 6,7 = Tariff2 ST,DST   Tariff9 0/1 = Weekend toggle (1 = Off-Peak during weekend)
  * Change rename "Data" to "Hash" and limit to 32 bits when receiving UNKNOWN IR protocol (see DECODE_HASH from IRremoteESP8266)
+ * Add command Gpios 255/All to show all available GPIO components (#6407)
  *
  * 6.6.0.11 20190907
  * Change Settings crc calculation allowing short term backward compatibility
diff --git a/sonoff/i18n.h b/sonoff/i18n.h
index e44b4a928..a6695fb73 100644
--- a/sonoff/i18n.h
+++ b/sonoff/i18n.h
@@ -604,12 +604,6 @@ const char kCodeImage[] PROGMEM = "sonoff|minimal|classic|sensors|knx|basic|disp
 // support.ino
 static const char kMonthNames[] = D_MONTH3LIST;
 
-const char kOptionOff[] PROGMEM = "OFF|" D_OFF "|" D_FALSE "|" D_STOP "|" D_CELSIUS ;
-const char kOptionOn[] PROGMEM = "ON|" D_ON "|" D_TRUE "|" D_START "|" D_FAHRENHEIT "|" D_USER ;
-const char kOptionToggle[] PROGMEM = "TOGGLE|" D_TOGGLE "|" D_ADMIN ;
-const char kOptionBlink[] PROGMEM = "BLINK|" D_BLINK ;
-const char kOptionBlinkOff[] PROGMEM = "BLINKOFF|" D_BLINKOFF ;
-
 // xdrv_02_webserver.ino
 #ifdef USE_WEBSERVER
 const char HTTP_SNS_TEMP[] PROGMEM = "{s}%s " D_TEMPERATURE "{m}%s&deg;%c{e}";                    // {s} = <tr><th>, {m} = </th><td>, {e} = </td></tr>
diff --git a/sonoff/support.ino b/sonoff/support.ino
index b9fec8651..cca75b377 100644
--- a/sonoff/support.ino
+++ b/sonoff/support.ino
@@ -761,25 +761,26 @@ bool DecodeCommand(const char* haystack, void (* const MyCommand[])(void))
   return false;
 }
 
+const char kOptions[] PROGMEM = "OFF|" D_OFF "|" D_FALSE "|" D_STOP "|" D_CELSIUS "|"              // 0
+                                "ON|" D_ON "|" D_TRUE "|" D_START "|" D_FAHRENHEIT "|" D_USER "|"  // 1
+                                "TOGGLE|" D_TOGGLE "|" D_ADMIN "|"                                 // 2
+                                "BLINK|" D_BLINK "|"                                               // 3
+                                "BLINKOFF|" D_BLINKOFF "|"                                         // 4
+                                "ALL" ;                                                            // 255
+
+const uint8_t sNumbers[] PROGMEM = { 0,0,0,0,0,
+                                     1,1,1,1,1,1,
+                                     2,2,2,
+                                     3,3,
+                                     4,4,
+                                     255 };
+
 int GetStateNumber(char *state_text)
 {
   char command[CMDSZ];
-  int state_number = -1;
-
-  if (GetCommandCode(command, sizeof(command), state_text, kOptionOff) >= 0) {
-    state_number = 0;
-  }
-  else if (GetCommandCode(command, sizeof(command), state_text, kOptionOn) >= 0) {
-    state_number = 1;
-  }
-  else if (GetCommandCode(command, sizeof(command), state_text, kOptionToggle) >= 0) {
-    state_number = 2;
-  }
-  else if (GetCommandCode(command, sizeof(command), state_text, kOptionBlink) >= 0) {
-    state_number = 3;
-  }
-  else if (GetCommandCode(command, sizeof(command), state_text, kOptionBlinkOff) >= 0) {
-    state_number = 4;
+  int state_number = GetCommandCode(command, sizeof(command), state_text, kOptions);
+  if (state_number >= 0) {
+    state_number = pgm_read_byte(sNumbers + state_number);
   }
   return state_number;
 }
diff --git a/sonoff/support_command.ino b/sonoff/support_command.ino
index c181a70bf..bd7107648 100644
--- a/sonoff/support_command.ino
+++ b/sonoff/support_command.ino
@@ -859,20 +859,19 @@ void CmndGpios(void)
   bool jsflg = false;
   for (uint32_t i = 0; i < sizeof(kGpioNiceList); i++) {
     midx = pgm_read_byte(kGpioNiceList + i);
-    if (!GetUsedInModule(midx, cmodule.io)) {
-      if (!jsflg) {
-        Response_P(PSTR("{\"" D_CMND_GPIOS "%d\":["), lines);
-      } else {
-        ResponseAppend_P(PSTR(","));
-      }
-      jsflg = true;
-      char stemp1[TOPSZ];
-      if ((ResponseAppend_P(PSTR("\"%d (%s)\""), midx, GetTextIndexed(stemp1, sizeof(stemp1), midx, kSensorNames)) > (LOGSZ - TOPSZ)) || (i == sizeof(kGpioNiceList) -1)) {
-        ResponseAppend_P(PSTR("]}"));
-        MqttPublishPrefixTopic_P(RESULT_OR_STAT, UpperCase(XdrvMailbox.command, XdrvMailbox.command));
-        jsflg = false;
-        lines++;
-      }
+    if ((XdrvMailbox.payload != 255) && GetUsedInModule(midx, cmodule.io)) { continue; }
+    if (!jsflg) {
+      Response_P(PSTR("{\"" D_CMND_GPIOS "%d\":["), lines);
+    } else {
+      ResponseAppend_P(PSTR(","));
+    }
+    jsflg = true;
+    char stemp1[TOPSZ];
+    if ((ResponseAppend_P(PSTR("\"%d (%s)\""), midx, GetTextIndexed(stemp1, sizeof(stemp1), midx, kSensorNames)) > (LOGSZ - TOPSZ)) || (i == sizeof(kGpioNiceList) -1)) {
+      ResponseAppend_P(PSTR("]}"));
+      MqttPublishPrefixTopic_P(RESULT_OR_STAT, UpperCase(XdrvMailbox.command, XdrvMailbox.command));
+      jsflg = false;
+      lines++;
     }
   }
   mqtt_data[0] = '\0';