diff --git a/src/WebContent.h b/src/WebContent.h
index b158106..3619581 100644
--- a/src/WebContent.h
+++ b/src/WebContent.h
@@ -44,6 +44,15 @@ const char index_html[] PROGMEM = R"rawliteral(
 
    <form method="POST" action="/upload" enctype="multipart/form-data"><input type="file" name="data"/><input type="submit" name="upload" value="Upload" title="Upload File"></form>
    
+    <h2>Edit RFID Mapping</h2>
+    <form id="editMappingForm">
+      <label for="rfid">RFID:</label>
+      <input type="text" id="rfid" name="rfid" required><br>
+      <label for="song">Song:</label>
+      <input type="text" id="song" name="song" required><br>
+      <button type="button" onclick="editMapping()">Update Mapping</button>
+    </form>
+
    <script>
     setInterval(getState, 4000);
     setInterval(updateProgress, 500); // Update progress every second
@@ -180,6 +189,20 @@ const char index_html[] PROGMEM = R"rawliteral(
 
    }
 
+   function editMapping() {
+        var rfid = document.getElementById('rfid').value;
+        var song = document.getElementById('song').value;
+        var xhr = new XMLHttpRequest();
+        xhr.open("POST", "/edit_mapping", true);
+        xhr.setRequestHeader("Content-Type", "application/x-www-form-urlencoded; charset=UTF-8");
+        xhr.send("rfid=" + encodeURIComponent(rfid) + "&song=" + encodeURIComponent(song));
+        xhr.onreadystatechange = function() {
+          if (xhr.readyState === 4 && xhr.status === 200) {
+            alert("Mapping updated successfully!");
+          }
+        };
+      }
+
   </script>
   </body>
 </html>)rawliteral";
\ No newline at end of file
diff --git a/src/main.cpp b/src/main.cpp
index af51aaf..432dd0f 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -144,7 +144,7 @@ void deactivateRFID()
 String humanReadableSize(const size_t bytes) {
   if (bytes < 1024) return String(bytes) + " B";
   else if (bytes < (1024 * 1024)) return String(bytes / 1024.0) + " KB";
-  else if (bytes < (1024 * 1024 * 1024)) return String(bytes / 1024.0 / 1024.0) + " MB";
+  else if (bytes < (1024 * 1024 * 1024)) return String(bytes / 1024.0 / 1024.0) + " MB";  
   else return String(bytes / 1024.0 / 1024.0 / 1024.0) + " GB";
 }
 
@@ -176,10 +176,11 @@ void handleUpload(AsyncWebServerRequest *request, String filename, size_t index,
 
 uint32_t getBatteryVoltageMv() {
   uint32_t voltage = analogReadMilliVolts(BAT_VOLTAGE_PIN);
+  voltage *= 2;//*2 because of the voltage divider.
   Serial.print("Battery Voltage: ");
-  Serial.println(voltage*2);
+  Serial.println(voltage);
   Serial.println(" mV");
-  return voltage*2;//*2 because of the voltage divider.
+  return voltage;
 }
 
 
@@ -365,6 +366,33 @@ String getState()
   return output;
 }
 
+// Function to save the rfid_map to the mapping file
+void saveMappingToFile(const char *filename) {
+  File file = SD.open(filename, FILE_WRITE);
+  if (file) {
+    for (const auto &pair : rfid_map) {
+      file.println(pair.first + "=" + pair.second);
+    }
+    file.close();
+    Serial.println("Mapping saved to file.");
+  } else {
+    Serial.println("Error opening file for writing.");
+  }
+}
+
+// Function to handle edit requests
+void editMapping(AsyncWebServerRequest *request) {
+  if (request->hasParam("rfid", true) && request->hasParam("song", true)) {
+    String rfid = request->getParam("rfid", true)->value();
+    String song = request->getParam("song", true)->value();
+    rfid_map[rfid] = song;
+    saveMappingToFile(mapping_file.c_str());
+    request->send(200, "text/plain", "Mapping updated");
+  } else {
+    request->send(400, "text/plain", "Invalid parameters");
+  }
+}
+
 std::map<String, String> readDataFromFile(const char *filename) {
   
   File file = SD.open(filename);
@@ -645,6 +673,8 @@ void setup()
 
     server.on("/volume", HTTP_POST, volume_action);
 
+    server.on("/edit_mapping", HTTP_POST, editMapping);
+
       // run handleUpload function when any file is uploaded
     server.on("/upload", HTTP_POST, [](AsyncWebServerRequest *request) {
         request->send(200);