diff --git a/README.md b/README.md
index a147762..26e0087 100644
--- a/README.md
+++ b/README.md
@@ -74,3 +74,4 @@ Build and push this container to ghcr
 - [x] sort videos most to least recent
 - [x] header on playlist page
 - [x] Choose database directory
+- [x] add extension to download
diff --git a/handlers.go b/handlers.go
index e04b9a9..3ef7bda 100644
--- a/handlers.go
+++ b/handlers.go
@@ -788,8 +788,8 @@ func makeNiceFilename(input string) string {
 	}
 
 	// Remove any remaining non-alphanumeric characters (except underscores)
-	reg := regexp.MustCompile("[^a-z0-9_\\.]+")
-	input = reg.ReplaceAllString(input, "")
+	reg := regexp.MustCompile("[^a-z0-9_.-]")
+	input = reg.ReplaceAllString(input, "x")
 
 	// Trim leading/trailing underscores
 	input = strings.Trim(input, "_")
@@ -849,7 +849,7 @@ func videoHandler(c echo.Context) error {
 			FPS:              fmt.Sprintf("%.1f", video.FPS),
 			Size:             humanSize(video.Size),
 			Filename:         video.Filename,
-			DownloadFilename: makeNiceFilename(orig.Title),
+			DownloadFilename: makeNiceFilename(orig.Title + filepath.Ext(tempURL.FilePath)),
 			StreamRate:       fmt.Sprintf("%.1f KiB/s", rate/1024),
 			TempURL:          tempURL,
 		})
@@ -869,7 +869,7 @@ func videoHandler(c echo.Context) error {
 			Kbps:             fmt.Sprintf("%.1f kbps", kbps),
 			Size:             humanSize(audio.Size),
 			Filename:         audio.Filename,
-			DownloadFilename: makeNiceFilename(orig.Title),
+			DownloadFilename: makeNiceFilename(orig.Title + filepath.Ext(tempURL.FilePath)),
 			StreamRate:       fmt.Sprintf("%.1f KiB/s", rate/1024),
 			TempURL:          tempURL,
 		})