diff --git a/internal/bootstrap/data/setting.go b/internal/bootstrap/data/setting.go
index 6f78f0e4..ac9f1b45 100644
--- a/internal/bootstrap/data/setting.go
+++ b/internal/bootstrap/data/setting.go
@@ -83,7 +83,13 @@ func initialSettings() {
 		{Key: conf.ImageTypes, Value: "jpg,tiff,jpeg,png,gif,bmp,svg,ico,swf,webp", Type: conf.TypeText, Group: model.PREVIEW, Flag: model.PRIVATE},
 		{Key: conf.OfficeTypes, Value: "doc,docx,xls,xlsx,ppt,pptx,pdf", Type: conf.TypeText, Group: model.PREVIEW, Flag: model.PRIVATE},
 		{Key: conf.ProxyTypes, Value: "m3u8", Type: conf.TypeText, Group: model.PREVIEW, Flag: model.PRIVATE},
-		{Key: conf.PdfViewerUrl, Value: "https://alist-org.github.io/pdf.js/web/viewer.html?file=$url", Type: conf.TypeString, Group: model.PREVIEW},
+		{Key: conf.OfficeViewers, Value: `{
+	"Microsoft":"https://view.officeapps.live.com/op/view.aspx?src=$url",
+	"Google":"https://docs.google.com/gview?url=$url&embedded=true",
+}`, Type: conf.TypeText, Group: model.PREVIEW},
+		{Key: conf.PdfViewers, Value: `{
+	"pdf.js":"https://alist-org.github.io/pdf.js/web/viewer.html?file=$url"
+}`, Type: conf.TypeText, Group: model.PREVIEW},
 		{Key: conf.AudioAutoplay, Value: "true", Type: conf.TypeBool, Group: model.PREVIEW},
 		{Key: conf.VideoAutoplay, Value: "true", Type: conf.TypeBool, Group: model.PREVIEW},
 		// global settings
diff --git a/internal/conf/const.go b/internal/conf/const.go
index eb5d7a13..a9fc0f80 100644
--- a/internal/conf/const.go
+++ b/internal/conf/const.go
@@ -26,7 +26,8 @@ const (
 	ImageTypes    = "image_types"
 	OfficeTypes   = "office_types"
 	ProxyTypes    = "proxy_types"
-	PdfViewerUrl  = "pdf_viewer_url"
+	OfficeViewers = "office_viewers"
+	PdfViewers    = "pdf_viewers"
 	AudioAutoplay = "audio_autoplay"
 	VideoAutoplay = "video_autoplay"