diff --git a/README.md b/README.md
index 01d0434..5d52ce3 100644
--- a/README.md
+++ b/README.md
@@ -223,8 +223,19 @@ You can pass it like this:
  
  $converter = new Converter($config);
  ```
- 
 
+To Debug the file handling (upload and download) you can activate the debug mode. By default Debug mode is disabled.
+You can pass it like this:
+
+ ```php
+ use RebaseData\Config\Config;
+ use RebaseData\Converter\Converter;
+ 
+ $config = new Config();
+ $config->setDebugMode(true);
+ 
+ $converter = new Converter($config);
+ ```
 
 Tests
 -----
diff --git a/src/Config/Config.php b/src/Config/Config.php
index f7338ee..73e6fa6 100644
--- a/src/Config/Config.php
+++ b/src/Config/Config.php
@@ -13,6 +13,7 @@ class Config
     private $cacheEnabled;
     private $cacheDirectory;
     private $useZipIfAvailable;
+    private $debugMode;
 
     public function __construct()
     {
@@ -20,6 +21,7 @@ public function __construct()
         $this->host = 'www.rebasedata.com';
         $this->cacheEnabled = false;
         $this->useZipIfAvailable = true;
+        $this->debugMode = false;
     }
 
     public function setProtocol(string $protocol)
@@ -27,22 +29,22 @@ public function setProtocol(string $protocol)
         $this->protocol = $protocol;
     }
 
-    public function getProtocol() : string
+    public function getProtocol(): string
     {
         return $this->protocol;
     }
 
-    public function setHost(string $host) : void
+    public function setHost(string $host): void
     {
         $this->host = $host;
     }
 
-    public function getHost() : string
+    public function getHost(): string
     {
         return $this->host;
     }
 
-    public function getWorkingDirectory()
+    public function getWorkingDirectory(): string
     {
         if ($this->workingDirectory === null) {
             $defaultWorkingDirectory = sys_get_temp_dir().DIRECTORY_SEPARATOR.'rebasedata-working-dir';
@@ -78,10 +80,10 @@ public function setApiKey($apiKey)
 
     public function setCacheEnabled($cacheEnabled)
     {
-        $this->cacheEnabled = (bool) $cacheEnabled;
+        $this->cacheEnabled = (bool)$cacheEnabled;
     }
 
-    public function getCacheEnabled()
+    public function getCacheEnabled(): bool
     {
         return $this->cacheEnabled;
     }
@@ -95,7 +97,7 @@ public function setCacheDirectory($cacheDirectory)
         $this->cacheDirectory = $cacheDirectory;
     }
 
-    public function getCacheDirectory()
+    public function getCacheDirectory(): string
     {
         if ($this->cacheDirectory === null) {
             $defaultCacheDirectory = $this->getWorkingDirectory().DIRECTORY_SEPARATOR.'cache';
@@ -110,13 +112,23 @@ public function getCacheDirectory()
         return $this->cacheDirectory;
     }
 
-    public function setUseZipIfAvailable(bool $useZipIfAvailable) : void
+    public function setUseZipIfAvailable(bool $useZipIfAvailable): void
     {
         $this->useZipIfAvailable = $useZipIfAvailable;
     }
 
-    public function getUseZipIfAvailable() : bool
+    public function getUseZipIfAvailable(): bool
     {
         return $this->useZipIfAvailable;
     }
+
+    public function setDebugMode(bool $debugMode): void
+    {
+        $this->debugMode = $debugMode;
+    }
+
+    public function getDebugMode(): bool
+    {
+        return $this->debugMode;
+    }
 }
diff --git a/src/Converter/Converter.php b/src/Converter/Converter.php
index 92902d9..c49f7d6 100644
--- a/src/Converter/Converter.php
+++ b/src/Converter/Converter.php
@@ -122,6 +122,11 @@ public function convertAndSaveToZipFile(array $inputFiles, string $format, strin
         $this->doConversion($inputFiles, $format, $zipFilePath, null, $options);
     }
 
+    /**
+     * @throws LogicException
+     * @throws RuntimeException
+     * @throws InvalidArgumentException
+     */
     private function doConversion(array $inputFiles, string $format, ?string $zipFilePath, ?string $targetDirectory, array $options = [])
     {
         CheckInputFilesService::execute($inputFiles);
@@ -190,22 +195,44 @@ private function doConversion(array $inputFiles, string $format, ?string $zipFil
         // Send request body
         foreach ($inputFiles as $inputFile) {
             $name = basename($inputFile->getName());
+            if ($this->config->getDebugMode()) {
+                $humanSize = $this->humanFileSize(filesize($inputFile->getPath()));
+                echo "\n\n[DEBUG] *** Processing file {$inputFile->getName()} [{$humanSize}] ***";
+            }
 
             $nameLength = pack('J', strlen($name));
 
             fwrite($socket, $nameLength);
             fwrite($socket, $name);
 
-            $contentLength = pack('J', filesize($inputFile->getPath()));
+            $fileSize = filesize($inputFile->getPath());
+            $contentLength = pack('J', $fileSize);
 
             fwrite ($socket, $contentLength);
 
+            $currentTransferSize = 0;
             $inputFileHandle = fopen($inputFile->getPath(), 'r');
+            $chunkSize = $fileSize > 10000 ? round($fileSize / 1000) : 1;
+
             while (!feof($inputFileHandle)) {
                 $chunk = fread($inputFileHandle, 2048);
 
+                if ($this->config->getDebugMode() && $chunkSize > 1) {
+                    $currentTransferSize += 2048;
+                    $percentage = round($currentTransferSize / $fileSize * 100);
+
+                    if ($currentTransferSize % $chunkSize === 0 && $percentage < 100) {
+                        echo "\n        *** uploading {$percentage}% ***";
+                    }
+                }
+
                 fwrite($socket, $chunk);
             }
+
+            if ($this->config->getDebugMode()) {
+                echo "\n[DEBUG] *** File {$inputFile->getName()} uploaded. ***";
+            }
+
             fclose($inputFileHandle);
         }
 
@@ -246,6 +273,10 @@ private function doConversion(array $inputFiles, string $format, ?string $zipFil
             throw new RuntimeException('Got error from API: '.$json['error']);
         }
 
+        if ($this->config->getDebugMode()) {
+            echo "\n\n[DEBUG] *** Handling response from {$this->config->getHost()} ***";
+        }
+
         // Handle response body
         if ($zipFilePath !== null) {
             // Read connection and write data to ZIP file
@@ -353,4 +384,46 @@ public function convertToFormatAndSaveAsZipFile(array $inputFiles, string $forma
     {
         $this->doConversion($inputFiles, $format, $zipFilePath, null, $options);
     }
+
+    /**
+     * Converts bytes into human-readable file size.
+     *
+     * @param string $bytes
+     * @return string human-readable file size (2,87 МB)
+     */
+    function humanFileSize(string $bytes): string
+    {
+        $bytes = floatval($bytes);
+        $unitMap = [
+            [
+                "unit" => "TB",
+                "value" => pow(1024, 4)
+            ],
+            [
+                "unit" => "GB",
+                "value" => pow(1024, 3)
+            ],
+            [
+                "unit" => "MB",
+                "value" => pow(1024, 2)
+            ],
+            [
+                "unit" => "KB",
+                "value" => 1024
+            ],
+            [
+                "unit" => "B",
+                "value" => 1
+            ],
+        ];
+
+        foreach ($unitMap as $item) {
+            if ($bytes >= $item["value"]) {
+                $result = round($bytes / $item["value"], 2). " " . $item["unit"];
+                break;
+            }
+        }
+
+        return $result ?? $bytes;
+    }
 }