diff --git a/index.h b/index.h
index a0cc5e8..6a0aff4 100644
--- a/index.h
+++ b/index.h
@@ -28,6 +28,12 @@ const char index_html[] PROGMEM = R"rawliteral(
   <button class="button" onclick="showSavedPixels()">Show Saved Pixels</button>
   <button class="button" onclick="location.href='/upload-page'">Upload Image</button>
   <br>
+  <div>
+    <label for="brightness">Brightness: </label>
+    <input type="range" id="brightness" min="0" max="100" value="100" onchange="updateBrightness()">
+    <span id="brightnessValue">100</span>
+  </div>
+  <br>
   <textarea id="jsonInput" placeholder="Paste your JSON image data here..."></textarea>
   <br>
   <button class="button" onclick="uploadAndDraw()">Upload and Draw</button>
@@ -46,6 +52,15 @@ const char index_html[] PROGMEM = R"rawliteral(
       xhr.setRequestHeader("Content-Type", "application/json");
       xhr.send(jsonData);
     }
+
+    function updateBrightness() {
+      var brightness = document.getElementById("brightness").value;
+      document.getElementById("brightnessValue").innerText = brightness;
+      var xhr = new XMLHttpRequest();
+      xhr.open("POST", "/brightness", true);
+      xhr.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
+      xhr.send("value=" + brightness);
+    }
   </script>
 </body>
 </html>
diff --git a/ledy.ino b/ledy.ino
index f405af0..c655c89 100644
--- a/ledy.ino
+++ b/ledy.ino
@@ -133,13 +133,13 @@ void scrollAllScrollableTexts(bool split_scroll_mode = false)
   }
 }
 
-void drawImageFromMemoryByIndex(unsigned char image_index, short pos_x, short pos_y, unsigned char dim_percentage = 0)
+void drawImageFromMemoryByIndex(unsigned char image_index, short pos_x, short pos_y, unsigned char brightness)
 {
 	Image* img = &saved_images[image_index];
 
-  auto dimBy = [dim_percentage](unsigned char color)
+  auto dimBy = [brightness](unsigned char color)
   {
-    return color * (100 - dim_percentage) / 100;
+    return color * brightness / 100;
   };
 
 	for (unsigned char y = 0; y < img->height; y++)
@@ -173,7 +173,7 @@ void loop()
 
   if (saved_images[0].width > 0)
   {
-    drawImageFromMemoryByIndex(0, 0, 0);
+    drawImageFromMemoryByIndex(0, 0, 0, brightness);
   }
   else
   {
diff --git a/prototypes.h b/prototypes.h
index dd3fc03..934a87a 100644
--- a/prototypes.h
+++ b/prototypes.h
@@ -9,9 +9,10 @@ extern Image saved_images[MAX_IMAGES_SAVED];
 extern unsigned char saved_images_count;
 extern TextNode text_nodes[MAX_TEXT_NODES_COUNT];
 extern Cursor cursor;
+extern unsigned char brightness;
 
 
-void drawImageFromMemoryByIndex(unsigned char image_index, short pos_x, short pos_y, unsigned char dim_percentage = 0);
+void drawImageFromMemoryByIndex(unsigned char image_index, short pos_x, short pos_y, unsigned char brightness = 100);
 void setPixel(short x, short y, uint32_t color);
 void start_server();
 void handle_server();
diff --git a/server.ino b/server.ino
index 20a25be..d8ce7a5 100644
--- a/server.ino
+++ b/server.ino
@@ -7,6 +7,7 @@
 
 const char* ssid = "PPIA";
 const char* password = "pawelpdaldonejta";
+unsigned char brightness = 100;
 
 WebServer server(80);
 
@@ -16,6 +17,13 @@ size_t fileContent_len = 0;
 String upload_error_message = "";
 
 
+void handleBrightness() {
+  if (server.hasArg("value")) {
+    brightness = server.arg("value").toInt();
+  }
+  server.send(200, "text/plain", "OK");
+}
+
 void handleRoot()
 {
   server.send(200, "text/html", index_html);
@@ -91,7 +99,7 @@ void handleBmpUpload() {
 void handleShowSaved()
 {
   pixels.clear();
-  drawImageFromMemoryByIndex(0, 0, 0, 100);
+  drawImageFromMemoryByIndex(0, 0, 0, brightness);
   pixels.show();
   server.send(200, "text/plain", "OK");
 }
@@ -108,6 +116,7 @@ void start_server()
   Serial.println(WiFi.localIP());
 
   server.on("/", handleRoot);
+  server.on("/brightness", HTTP_POST, handleBrightness);
   server.on("/show-saved", handleShowSaved);
   server.on("/upload-page", HTTP_GET, handleUploadPage);
   server.on("/upload-bmp", HTTP_POST, []() {