diff --git a/crates/engine/src/cmd/comp.rs b/crates/engine/src/cmd/comp.rs
index 8bc0931f8..8f44ebd3d 100644
--- a/crates/engine/src/cmd/comp.rs
+++ b/crates/engine/src/cmd/comp.rs
@@ -272,6 +272,20 @@ fn poster(s: &mut Session, p: &Value) -> Result<Value> {
     Ok(Value::Null)
 }
 
+fn delete_all_markers(s: &mut Session, p: &Value) -> Result<Value> {
+    let cid = comp_id(s, p)?;
+    s.edit("Delete All Markers", None, |proj, _| {
+        proj.comp_mut(cid).ok_or(EngineError::NoComp)?.markers.clear();
+        Ok(())
+    })?;
+    Ok(Value::Null)
+}
+
+fn has_comp_markers(s: &Session) -> std::result::Result<(), String> {
+    let c = s.active_comp().ok_or("no composition")?;
+    if !c.markers.is_empty() { Ok(()) } else { Err("the composition has no markers".into()) }
+}
+
 pub fn specs() -> Vec<CommandSpec> {
     vec![
         cmd!(
@@ -299,5 +313,6 @@ pub fn specs() -> Vec<CommandSpec> {
         cmd!("comp.workArea", "Set Work Area", [], None, "{start?, end?, set?: begin|end (at CTI)}", has_comp, work_area),
         cmd!("comp.setSwitch", "Composition Switch", [], None, "{switch: hideShy|motionBlur|frameBlending|draft3d, value?}", has_comp, comp_switch),
         cmd!("comp.addMarker", "Add Marker", [], Some("Num*"), "{time?, comment?}", has_comp, add_marker),
+        cmd!("comp.deleteAllMarkers", "Delete All Markers", [], None, "{comp?}", has_comp_markers, delete_all_markers),
     ]
 }
diff --git a/crates/engine/src/cmd/layer_menu.rs b/crates/engine/src/cmd/layer_menu.rs
index e0c4efc72..455873e0b 100644
--- a/crates/engine/src/cmd/layer_menu.rs
+++ b/crates/engine/src/cmd/layer_menu.rs
@@ -19,9 +19,10 @@ fn has_masks(s: &Session) -> std::result::Result<(), String> {
 }
 
 fn has_markers(s: &Session) -> std::result::Result<(), String> {
-    has_layers(s)?;
     let c = s.active_comp().ok_or("no composition")?;
-    if s.state.selected_layers.iter().filter_map(|l| c.layer(*l)).any(|l| !l.markers.is_empty()) {
+    if s.state.selected_layers.is_empty() {
+        if !c.markers.is_empty() { Ok(()) } else { Err("the composition has no markers".into()) }
+    } else if s.state.selected_layers.iter().filter_map(|l| c.layer(*l)).any(|l| !l.markers.is_empty()) {
         Ok(())
     } else {
         Err("the selected layers have no markers".into())
@@ -596,6 +597,13 @@ fn markers_lock(s: &mut Session, p: &Value) -> Result<Value> {
 
 fn delete_all_markers(s: &mut Session, p: &Value) -> Result<Value> {
     let (cid, ids) = layers_p(s, p)?;
+    if ids.is_empty() {
+        s.edit("Delete All Markers", None, |proj, _| {
+            proj.comp_mut(cid).ok_or(EngineError::NoComp)?.markers.clear();
+            Ok(())
+        })?;
+        return Ok(Value::Null);
+    }
     s.edit("Delete All Markers", None, |proj, _| {
         for l in proj.comp_mut(cid).ok_or(EngineError::NoComp)?.layers.iter_mut_where(|l| ids.contains(&l.id) && !l.markers_locked) {
             l.markers.clear();
diff --git a/crates/engine/src/tests/markers.rs b/crates/engine/src/tests/markers.rs
index 66aac5694..87792390f 100644
--- a/crates/engine/src/tests/markers.rs
+++ b/crates/engine/src/tests/markers.rs
@@ -194,3 +194,30 @@ fn layer_add_marker_without_selection_adds_comp_marker() {
     assert!((comp.markers[0].time.seconds() - 1.5).abs() < 1e-9);
     assert_eq!(comp.markers[0].comment, "timeline marker");
 }
+
+#[test]
+fn comp_delete_all_markers_with_undo() {
+    let (mut s, _) = setup();
+    s.execute("comp.addMarker", json!({"time": 1.0, "comment": "m1"})).unwrap();
+    s.execute("comp.addMarker", json!({"time": 2.0, "comment": "m2"})).unwrap();
+    assert_eq!(s.active_comp().unwrap().markers.len(), 2);
+    s.execute("comp.deleteAllMarkers", json!({})).unwrap();
+    assert!(s.active_comp().unwrap().markers.is_empty());
+    s.execute("edit.undo", json!({})).unwrap();
+    assert_eq!(s.active_comp().unwrap().markers.len(), 2);
+    s.execute("edit.redo", json!({})).unwrap();
+    assert!(s.active_comp().unwrap().markers.is_empty());
+}
+
+#[test]
+fn layer_delete_all_markers_without_selection_clears_comp_markers() {
+    let (mut s, _) = setup();
+    s.execute("comp.addMarker", json!({"time": 1.0, "comment": "m1"})).unwrap();
+    s.execute("comp.addMarker", json!({"time": 2.0, "comment": "m2"})).unwrap();
+    s.execute("edit.deselectAll", json!({})).unwrap();
+    assert!(s.state.selected_layers.is_empty());
+    s.execute("layer.deleteAllMarkers", json!({})).unwrap();
+    assert!(s.active_comp().unwrap().markers.is_empty());
+    s.execute("edit.undo", json!({})).unwrap();
+    assert_eq!(s.active_comp().unwrap().markers.len(), 2);
+}
diff --git a/crates/ui-egui/src/panels/markers_ui.rs b/crates/ui-egui/src/panels/markers_ui.rs
index 2c21a293b..54f06d6b6 100644
--- a/crates/ui-egui/src/panels/markers_ui.rs
+++ b/crates/ui-egui/src/panels/markers_ui.rs
@@ -373,6 +373,8 @@ fn marker(app: &mut EffectcraftApp, ui: &mut egui::Ui, p: &egui::Painter, comp:
         run(ui, "Delete This Marker", "markers.delete", r.params(), app);
         if let Some(l) = r.layer {
             run(ui, "Delete All Markers", "layer.deleteAllMarkers", json!({"layers": [l]}), app);
+        } else {
+            run(ui, "Delete All Markers", "comp.deleteAllMarkers", json!({}), app);
         }
     });
 }