diff --git a/src/server/event.rs b/src/server/event.rs
index ea2277c..ba31797 100644
--- a/src/server/event.rs
+++ b/src/server/event.rs
@@ -472,8 +472,8 @@ pub(super) fn update_surface_viewport(
     let dims = &window_data.attrs.dims;
     let size_hints = &window_data.attrs.size_hints;
 
-    let width = (dims.width as f64 / scale_factor.0) as i32;
-    let height = (dims.height as f64 / scale_factor.0) as i32;
+    let width = (dims.width as f64 / scale_factor.0).ceil() as i32;
+    let height = (dims.height as f64 / scale_factor.0).ceil() as i32;
     if width > 0 && height > 0 {
         viewport.set_destination(width, height);
     }
diff --git a/src/server/tests.rs b/src/server/tests.rs
index 68495d0..13492cd 100644
--- a/src/server/tests.rs
+++ b/src/server/tests.rs
@@ -2300,8 +2300,8 @@ fn fractional_scale_small_popup() {
     {
         let data = f.testwl.get_surface_data(toplevel_id).unwrap();
         let viewport = data.viewport.as_ref().expect("Missing viewport");
-        assert_eq!(viewport.width, 66);
-        assert_eq!(viewport.height, 66);
+        assert_eq!(viewport.width, 67);
+        assert_eq!(viewport.height, 67);
     }
 
     let popup = Window::new(2);