diff --git a/app/src/main/kotlin/com/simplemobiletools/gallery/dialogs/RenameFileDialog.kt b/app/src/main/kotlin/com/simplemobiletools/gallery/dialogs/RenameFileDialog.kt
index 9f78a797a..92e7a99c7 100644
--- a/app/src/main/kotlin/com/simplemobiletools/gallery/dialogs/RenameFileDialog.kt
+++ b/app/src/main/kotlin/com/simplemobiletools/gallery/dialogs/RenameFileDialog.kt
@@ -37,20 +37,24 @@ class RenameFileDialog(val activity: SimpleActivity, val file: File, val callbac
             setCanceledOnTouchOutside(true)
             show()
             getButton(AlertDialog.BUTTON_POSITIVE).setOnClickListener({
-                val fileName = view.file_name.value
+                val filename = view.file_name.value
                 val extension = view.file_extension.value
 
-                if (fileName.isEmpty() || extension.isEmpty()) {
+                if (filename.isEmpty()) {
                     context.toast(R.string.filename_cannot_be_empty)
                     return@setOnClickListener
                 }
 
-                if (!fileName.isAValidFilename()) {
-                    context.toast(R.string.invalid_name)
+                if (extension.isEmpty()) {
+                    context.toast(R.string.extension_cannot_be_empty)
                     return@setOnClickListener
                 }
 
-                val newFile = File(file.parent, "$fileName.$extension")
+                val newFile = File(file.parent, "$filename.$extension")
+                if (!newFile.name.isAValidFilename()) {
+                    context.toast(R.string.invalid_name)
+                    return@setOnClickListener
+                }
 
                 if (context.needsStupidWritePermissions(file.absolutePath)) {
                     if (activity.isShowingPermDialog(file))
diff --git a/app/src/main/kotlin/com/simplemobiletools/gallery/dialogs/SaveAsDialog.kt b/app/src/main/kotlin/com/simplemobiletools/gallery/dialogs/SaveAsDialog.kt
index 1cfc52470..ea85e4760 100644
--- a/app/src/main/kotlin/com/simplemobiletools/gallery/dialogs/SaveAsDialog.kt
+++ b/app/src/main/kotlin/com/simplemobiletools/gallery/dialogs/SaveAsDialog.kt
@@ -17,8 +17,18 @@ class SaveAsDialog(val activity: Activity, val path: String, val callback: (save
         val view = LayoutInflater.from(activity).inflate(R.layout.dialog_save_as, null)
         view.apply {
             file_path.text = activity.humanizePath(realPath)
-            file_name.setText(path.getFilenameFromPath())
 
+            val fullName = path.getFilenameFromPath()
+            val dotAt = fullName.lastIndexOf(".")
+            var name = fullName
+
+            if (dotAt > 0) {
+                name = fullName.substring(0, dotAt)
+                val extension = fullName.substring(dotAt + 1)
+                view.file_extension.setText(extension)
+            }
+
+            file_name.setText(name)
             file_path.setOnClickListener {
                 FilePickerDialog(activity, realPath, false, false, listener = object : FilePickerDialog.OnFilePickerListener {
                     override fun onSuccess(pickedPath: String) {
@@ -43,19 +53,25 @@ class SaveAsDialog(val activity: Activity, val path: String, val callback: (save
             show()
             getButton(AlertDialog.BUTTON_POSITIVE).setOnClickListener({
                 val filename = view.file_name.value
+                val extension = view.file_extension.value
 
                 if (filename.isEmpty()) {
                     context.toast(R.string.filename_cannot_be_empty)
                     return@setOnClickListener
                 }
 
-                if (!filename.isAValidFilename()) {
+                if (extension.isEmpty()) {
+                    context.toast(R.string.extension_cannot_be_empty)
+                    return@setOnClickListener
+                }
+
+                val newFile = File(realPath, "$filename.$extension")
+                if (!newFile.name.isAValidFilename()) {
                     context.toast(R.string.filename_invalid_characters)
                     return@setOnClickListener
                 }
 
-                val newPath = File(realPath, filename).absolutePath
-                callback.invoke(newPath)
+                callback.invoke(newFile.absolutePath)
                 dismiss()
             })
         }
diff --git a/app/src/main/res/layout/dialog_save_as.xml b/app/src/main/res/layout/dialog_save_as.xml
index f94203323..d3777bc2b 100644
--- a/app/src/main/res/layout/dialog_save_as.xml
+++ b/app/src/main/res/layout/dialog_save_as.xml
@@ -30,4 +30,17 @@
         android:layout_marginBottom="@dimen/activity_margin"
         android:singleLine="true"/>
 
+    <TextView
+        android:id="@+id/file_extension_label"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:text="@string/extension"/>
+
+    <EditText
+        android:id="@+id/file_extension"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_marginBottom="@dimen/activity_margin"
+        android:singleLine="true"/>
+
 </LinearLayout>
diff --git a/app/src/main/res/values-de/strings.xml b/app/src/main/res/values-de/strings.xml
index f2154b366..9603538f5 100644
--- a/app/src/main/res/values-de/strings.xml
+++ b/app/src/main/res/values-de/strings.xml
@@ -81,6 +81,7 @@
     <string name="filename_cannot_be_empty">Dateiname darf nicht leer sein</string>
     <string name="filename_invalid_characters">Filename contains invalid characters</string>
     <string name="extension">Dateiendung</string>
+    <string name="extension_cannot_be_empty">Extension cannot be empty</string>
 
     <!-- Sorting -->
     <string name="sort_by">Sortieren nach</string>
diff --git a/app/src/main/res/values-es/strings.xml b/app/src/main/res/values-es/strings.xml
index 21d859f9f..902df993c 100644
--- a/app/src/main/res/values-es/strings.xml
+++ b/app/src/main/res/values-es/strings.xml
@@ -81,6 +81,7 @@
     <string name="filename_cannot_be_empty">El nombre de archivo no puede estar vacío</string>
     <string name="filename_invalid_characters">Filename contains invalid characters</string>
     <string name="extension">Extensión</string>
+    <string name="extension_cannot_be_empty">Extension cannot be empty</string>
 
     <!-- Sorting -->
     <string name="sort_by">Ordenar por</string>
diff --git a/app/src/main/res/values-it/strings.xml b/app/src/main/res/values-it/strings.xml
index e7bb7661d..731a6aa11 100644
--- a/app/src/main/res/values-it/strings.xml
+++ b/app/src/main/res/values-it/strings.xml
@@ -81,6 +81,7 @@
     <string name="filename_cannot_be_empty">Il nome del file non deve essere vuoto</string>
     <string name="filename_invalid_characters">Il nome contiene caratteri non validi</string>
     <string name="extension">Estensione</string>
+    <string name="extension_cannot_be_empty">Extension cannot be empty</string>
 
     <!-- Sorting -->
     <string name="sort_by">Ordina per</string>
diff --git a/app/src/main/res/values-ja/strings.xml b/app/src/main/res/values-ja/strings.xml
index 5726bd372..7aa0308b6 100644
--- a/app/src/main/res/values-ja/strings.xml
+++ b/app/src/main/res/values-ja/strings.xml
@@ -81,6 +81,7 @@
     <string name="filename_cannot_be_empty">ファイル名は空にできません</string>
     <string name="filename_invalid_characters">ファイル名に無効な文字が含まれています</string>
     <string name="extension">拡張</string>
+    <string name="extension_cannot_be_empty">Extension cannot be empty</string>
 
     <!-- Sorting -->
     <string name="sort_by">並び替え</string>
diff --git a/app/src/main/res/values-pt-rPT/strings.xml b/app/src/main/res/values-pt-rPT/strings.xml
index 14f5cb9c1..f6d56f4f8 100644
--- a/app/src/main/res/values-pt-rPT/strings.xml
+++ b/app/src/main/res/values-pt-rPT/strings.xml
@@ -81,6 +81,7 @@
     <string name="filename_cannot_be_empty">O nome do ficheiro não pode estar vazio</string>
     <string name="filename_invalid_characters">O nome do ficheiro contém caracteres inválidos</string>
     <string name="extension">Extensão</string>
+    <string name="extension_cannot_be_empty">Extension cannot be empty</string>
 
     <!-- Sorting -->
     <string name="sort_by">Ordenar por</string>
diff --git a/app/src/main/res/values-ru/strings.xml b/app/src/main/res/values-ru/strings.xml
index 318ce824f..63a47dfa9 100644
--- a/app/src/main/res/values-ru/strings.xml
+++ b/app/src/main/res/values-ru/strings.xml
@@ -82,6 +82,7 @@
     <string name="filename_cannot_be_empty">Имя файла не может быть пустым</string>
     <string name="filename_invalid_characters">Имя файла содержит недопустимые символы</string>
     <string name="extension">Расширение</string>
+    <string name="extension_cannot_be_empty">Extension cannot be empty</string>
 
     <!-- Sorting -->
     <string name="sort_by">Сортировать по</string>
diff --git a/app/src/main/res/values-sv/strings.xml b/app/src/main/res/values-sv/strings.xml
index 1bb236c43..f463aa355 100644
--- a/app/src/main/res/values-sv/strings.xml
+++ b/app/src/main/res/values-sv/strings.xml
@@ -81,6 +81,7 @@
     <string name="filename_cannot_be_empty">Du måste ange ett filnamn</string>
     <string name="filename_invalid_characters">Filename contains invalid characters</string>
     <string name="extension">Filändelse</string>
+    <string name="extension_cannot_be_empty">Extension cannot be empty</string>
 
     <!-- Sorting -->
     <string name="sort_by">Sort by</string>
diff --git a/app/src/main/res/values-zh/strings.xml b/app/src/main/res/values-zh/strings.xml
index 138bdd6b3..d23948606 100644
--- a/app/src/main/res/values-zh/strings.xml
+++ b/app/src/main/res/values-zh/strings.xml
@@ -82,6 +82,7 @@
     <string name="filename_cannot_be_empty">文件名不能为空</string>
     <string name="filename_invalid_characters">文件名包含非法字符</string>
     <string name="extension">扩展名</string>
+    <string name="extension_cannot_be_empty">Extension cannot be empty</string>
 
     <!-- Sorting -->
     <string name="sort_by">排序方式</string>
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index 8e022c503..f55d2e886 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -81,6 +81,7 @@
     <string name="filename_cannot_be_empty">Filename cannot be empty</string>
     <string name="filename_invalid_characters">Filename contains invalid characters</string>
     <string name="extension">Extension</string>
+    <string name="extension_cannot_be_empty">Extension cannot be empty</string>
 
     <!-- Sorting -->
     <string name="sort_by">Sort by</string>