diff --git a/docs/changelog.md b/docs/changelog.md
index d43a4db5e..e23d619e8 100644
--- a/docs/changelog.md
+++ b/docs/changelog.md
@@ -114,6 +114,7 @@ As features stabilize some brief notes about them will accumulate here.
   immediately with the default `exit_behavior` setting. Now ssh sessions
   override `exit_behavior="CloseOnCleanExit"` while connecting so that error
   information can be displayed. #3941
+* Divide by zero panic with lots of splits and resizing panes. #3921
 
 #### Updated
 * Bundled harfbuzz to 8.0.0
diff --git a/mux/src/tab.rs b/mux/src/tab.rs
index 1d9163182..324056c27 100644
--- a/mux/src/tab.rs
+++ b/mux/src/tab.rs
@@ -1177,8 +1177,14 @@ impl TabInner {
     }
 
     fn apply_pane_size(&mut self, pane_size: TerminalSize, cursor: &mut Cursor) {
-        let cell_width = pane_size.pixel_width / pane_size.cols;
-        let cell_height = pane_size.pixel_height / pane_size.rows;
+        let cell_width = pane_size
+            .pixel_width
+            .checked_div(pane_size.cols)
+            .unwrap_or(1);
+        let cell_height = pane_size
+            .pixel_height
+            .checked_div(pane_size.rows)
+            .unwrap_or(1);
         if let Ok(Some(node)) = cursor.node_mut() {
             // Adjust the size of the node; we preserve the size of the first
             // child and adjust the second, so if we are split down the middle