diff --git a/flake.nix b/flake.nix
index beaabaf..fc03010 100644
--- a/flake.nix
+++ b/flake.nix
@@ -15,7 +15,7 @@
 					packages = rec {
 						slenpaste = pkgs.buildGoModule {
 							pname          = "slenpaste";
-							version        = "0.1.0";
+							version        = "0.1.1";
 							src            = ./.;
 							goPackagePath  = "github.com/slendidev/slenpaste";
 							vendorHash     = null;
diff --git a/main.go b/main.go
index a4e7861..ca34585 100644
--- a/main.go
+++ b/main.go
@@ -73,45 +73,50 @@ func uploadHandler(w http.ResponseWriter, r *http.Request) {
 	}
 
 	var reader io.Reader
+	var ext    string
 
+	// handle multipart file upload
 	contentType := r.Header.Get("Content-Type")
 	if strings.HasPrefix(contentType, "multipart/form-data") {
 		if err := r.ParseMultipartForm(10 << 20); err == nil {
-			if file, _, err := r.FormFile("file"); err == nil {
+			if file, header, err := r.FormFile("file"); err == nil {
 				defer file.Close()
 				reader = file
+				ext = filepath.Ext(header.Filename)
 			}
 		}
 	}
+
+	// fallback to body upload
 	if reader == nil {
 		reader = r.Body
 		defer r.Body.Close()
 	}
 
-	expVal := r.URL.Query().Get("expiry")
-	var dur time.Duration
-	var onView bool
-	switch expVal {
-	case "view":
-		onView = true
-	case "0":
-		// no expiry
-	default:
-		dur, _ = time.ParseDuration(expVal)
+	// default extension
+	if ext == "" {
+		ext = ".txt"
 	}
 
-	id := randomID(6)
+	// generate ID and filename
+	id       := randomID(6)
+	filename := id + ext
+
+	// ensure storage dir
 	if err := os.MkdirAll(staticDir, 0755); err != nil {
 		http.Error(w, "Server error", http.StatusInternalServerError)
 		return
 	}
-	path := filepath.Join(staticDir, id)
+	path := filepath.Join(staticDir, filename)
+
+	// save file
 	out, err := os.Create(path)
 	if err != nil {
 		http.Error(w, "Save error", http.StatusInternalServerError)
 		return
 	}
 	defer out.Close()
+
 	n, err := io.Copy(out, reader)
 	if err != nil {
 		http.Error(w, "Write error", http.StatusInternalServerError)
@@ -123,16 +128,26 @@ func uploadHandler(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	if dur > 0 || onView {
-		m := meta{ExpireOnView: onView}
-		if dur > 0 {
-			m.Expiry = time.Now().Add(dur)
+	// write metadata if needed
+	expVal := r.URL.Query().Get("expiry")
+	var m meta
+	switch expVal {
+	case "view":
+		m.ExpireOnView = true
+	case "0":
+		// no expiry
+	default:
+		if d, err := time.ParseDuration(expVal); err == nil {
+			m.Expiry = time.Now().Add(d)
 		}
+	}
+	if !m.Expiry.IsZero() || m.ExpireOnView {
 		metaBytes, _ := json.Marshal(m)
 		_ = os.WriteFile(path+".json", metaBytes, 0644)
 	}
 
-	fmt.Fprintf(w, "http://%s/%s\n", domain, id)
+	// respond with URL including extension
+	fmt.Fprintf(w, "http://%s/%s\n", domain, filename)
 }
 
 func viewHandler(w http.ResponseWriter, r *http.Request) {
@@ -141,7 +156,7 @@ func viewHandler(w http.ResponseWriter, r *http.Request) {
 		indexHandler(w, r)
 		return
 	}
-	path := filepath.Join(staticDir, id)
+	path     := filepath.Join(staticDir, id)
 	metaPath := path + ".json"
 
 	// load and enforce metadata
@@ -172,11 +187,11 @@ func viewHandler(w http.ResponseWriter, r *http.Request) {
 }
 
 func main() {
-	flag.StringVar(&domain, "domain", "localhost:8080", "domain name for URLs")
-	flag.StringVar(&listenAddr, "listen", "0.0.0.0:8080", "listen address")
-	flag.StringVar(&staticDir, "static", "static", "directory to save pastes")
-	flag.DurationVar(&expireDur, "expire", 0, "time after which paste expires (e.g. 5m, 1h)")
-	flag.BoolVar(&expireOnView, "expire-on-view", false, "delete paste after it's viewed once")
+	flag.StringVar(&domain,     "domain",         "localhost:8080", "domain name for URLs")
+	flag.StringVar(&listenAddr, "listen",         "0.0.0.0:8080",  "listen address")
+	flag.StringVar(&staticDir,  "static",         "static",        "directory to save pastes")
+	flag.DurationVar(&expireDur, "expire",         0,                "time after which paste expires (e.g. 5m, 1h)")
+	flag.BoolVar(&expireOnView, "expire-on-view", false,            "delete paste after it's viewed once")
 	flag.Parse()
 
 	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {