diff --git a/pkg/modules/pdfengines/routes.go b/pkg/modules/pdfengines/routes.go
index dd56201f..5baabed9 100644
--- a/pkg/modules/pdfengines/routes.go
+++ b/pkg/modules/pdfengines/routes.go
@@ -158,7 +158,12 @@ func convertRoute(engine gotenberg.PdfEngine) api.Route {
 			outputPaths := make([]string, len(inputPaths))
 
 			for i, inputPath := range inputPaths {
-				outputPaths[i] = ctx.GeneratePath(strings.TrimSuffix(filepath.Base(inputPath), filepath.Ext(inputPath)), ".pdf")
+				if len(outputPaths) > 1 {
+					// If .zip archive, keep the original filenames.
+					outputPaths[i] = ctx.GeneratePath(strings.TrimSuffix(filepath.Base(inputPath), filepath.Ext(inputPath)), ".pdf")
+				} else {
+					outputPaths[i] = ctx.GeneratePath("", ".pdf")
+				}
 
 				err = engine.Convert(ctx, ctx.Log(), pdfFormats, inputPath, outputPaths[i])
 				if err != nil {
diff --git a/pkg/modules/pdfengines/routes_test.go b/pkg/modules/pdfengines/routes_test.go
index 3766c0c9..46b5d8b0 100644
--- a/pkg/modules/pdfengines/routes_test.go
+++ b/pkg/modules/pdfengines/routes_test.go
@@ -418,7 +418,6 @@ func TestConvertHandler(t *testing.T) {
 			expectError:            false,
 			expectHttpError:        false,
 			expectOutputPathsCount: 1,
-			expectOutputPaths:      []string{"/file.pdf"},
 		},
 		{
 			scenario: "success with PDF/A & PDF/UA form fields (many files)",