diff --git a/tasmota/include/tasmota.h b/tasmota/include/tasmota.h
index 0ec8fa05f..a9e21c796 100644
--- a/tasmota/include/tasmota.h
+++ b/tasmota/include/tasmota.h
@@ -195,7 +195,9 @@ const uint8_t OTA_ATTEMPTS = 10;            // Number of times to try fetching t
 const uint8_t OTA_ATTEMPTS = 5;             // Number of times to try fetching the new firmware
 #endif  // ESP8266
 
-const uint16_t INPUT_BUFFER_SIZE = 520;     // Max number of characters in serial command buffer
+const uint16_t INPUT_BUFFER_SIZE = 520;     // Max number of characters in Tasmota serial command buffer
+const uint16_t MIN_INPUT_BUFFER_SIZE = 256;     // Max number of characters in Tasmota serial command buffer
+const uint16_t MAX_INPUT_BUFFER_SIZE = 2048; // Max number of characters in Arduino serial command buffer
 const uint16_t FLOATSZ = 16;                // Max number of characters in float result from dtostrfd (max 32)
 const uint16_t CMDSZ = 24;                  // Max number of characters in command
 const uint16_t TOPSZ = 151;                 // Max number of characters in topic string
diff --git a/tasmota/tasmota_support/support_command.ino b/tasmota/tasmota_support/support_command.ino
index 22ebd743a..e29c3ccb9 100644
--- a/tasmota/tasmota_support/support_command.ino
+++ b/tasmota/tasmota_support/support_command.ino
@@ -1830,16 +1830,19 @@ void CmndSerialConfig(void)
 
 void CmndSerialBuffer(void) {
   // Allow non-pesistent serial receive buffer size change
-  //   between 256 (default) and 520 (INPUT_BUFFER_SIZE) characters
+  //   between MIN_INPUT_BUFFER_SIZE and MAX_INPUT_BUFFER_SIZE characters
   size_t size = 0;
   if (XdrvMailbox.data_len > 0) {
     size = XdrvMailbox.payload;
-    if (XdrvMailbox.payload < 256) {
-      size = 256;
-    }
-    if ((1 == XdrvMailbox.payload) || (XdrvMailbox.payload > INPUT_BUFFER_SIZE)) {
+    if (1 == XdrvMailbox.payload) {
       size = INPUT_BUFFER_SIZE;
     }
+    else if (XdrvMailbox.payload < MIN_INPUT_BUFFER_SIZE) {
+      size = MIN_INPUT_BUFFER_SIZE;
+    }
+    else if (XdrvMailbox.payload > MAX_INPUT_BUFFER_SIZE) {
+      size = MAX_INPUT_BUFFER_SIZE;
+    }
     Serial.setRxBufferSize(size);
   }
 #ifdef ESP8266