diff --git a/esp3d/src/modules/filesystem/esp_filesystem.h b/esp3d/src/modules/filesystem/esp_filesystem.h
index 3a0ae769..6867391c 100644
--- a/esp3d/src/modules/filesystem/esp_filesystem.h
+++ b/esp3d/src/modules/filesystem/esp_filesystem.h
@@ -80,10 +80,7 @@ public:
     static void end();
     static size_t totalBytes();
     static size_t usedBytes();
-    static size_t freeBytes()
-    {
-        return totalBytes()-usedBytes();
-    };
+    static size_t freeBytes();
     static size_t max_update_size();
     static const char * FilesystemName();
     static bool format();
diff --git a/esp3d/src/modules/filesystem/flash/fat_esp32_filesystem.cpp b/esp3d/src/modules/filesystem/flash/fat_esp32_filesystem.cpp
index 4863e971..3db4502b 100644
--- a/esp3d/src/modules/filesystem/flash/fat_esp32_filesystem.cpp
+++ b/esp3d/src/modules/filesystem/flash/fat_esp32_filesystem.cpp
@@ -38,6 +38,11 @@ void ESP_FileSystem::end()
     _started = false;
 }
 
+size_t ESP_FileSystem::freeBytes()
+{
+    return FFat.freeBytes();
+}
+
 size_t ESP_FileSystem::totalBytes()
 {
     return FFat.totalBytes();
diff --git a/esp3d/src/modules/filesystem/flash/littlefs_esp8266_filesystem .cpp b/esp3d/src/modules/filesystem/flash/littlefs_esp8266_filesystem .cpp
index 26b309cc..ee0ceb31 100644
--- a/esp3d/src/modules/filesystem/flash/littlefs_esp8266_filesystem .cpp	
+++ b/esp3d/src/modules/filesystem/flash/littlefs_esp8266_filesystem .cpp	
@@ -38,6 +38,11 @@ void ESP_FileSystem::end()
     LittleFS.end();
 }
 
+size_t ESP_FileSystem::freeBytes()
+{
+    return totalBytes() - usedBytes();
+}
+
 size_t ESP_FileSystem::totalBytes()
 {
     fs::FSInfo info;
diff --git a/esp3d/src/modules/filesystem/flash/spiffs_esp32_filesystem.cpp b/esp3d/src/modules/filesystem/flash/spiffs_esp32_filesystem.cpp
index 1945d09b..31ce0110 100644
--- a/esp3d/src/modules/filesystem/flash/spiffs_esp32_filesystem.cpp
+++ b/esp3d/src/modules/filesystem/flash/spiffs_esp32_filesystem.cpp
@@ -36,6 +36,11 @@ void ESP_FileSystem::end()
     SPIFFS.end();
 }
 
+size_t ESP_FileSystem::freeBytes()
+{
+    return totalBytes() - usedBytes();
+}
+
 size_t ESP_FileSystem::totalBytes()
 {
     return SPIFFS.totalBytes();
diff --git a/esp3d/src/modules/filesystem/flash/spiffs_esp8266_filesystem.cpp b/esp3d/src/modules/filesystem/flash/spiffs_esp8266_filesystem.cpp
index 0c925c37..41a9b4e4 100644
--- a/esp3d/src/modules/filesystem/flash/spiffs_esp8266_filesystem.cpp
+++ b/esp3d/src/modules/filesystem/flash/spiffs_esp8266_filesystem.cpp
@@ -36,6 +36,11 @@ void ESP_FileSystem::end()
     SPIFFS.end();
 }
 
+size_t ESP_FileSystem::freeBytes()
+{
+    return totalBytes() - usedBytes();
+}
+
 size_t ESP_FileSystem::totalBytes()
 {
     fs::FSInfo info;