diff --git a/crates/tools/src/lib.rs b/crates/tools/src/lib.rs
index 29b77f38e..a87eb2cb7 100644
--- a/crates/tools/src/lib.rs
+++ b/crates/tools/src/lib.rs
@@ -392,6 +392,10 @@ impl ToolContext<'_> {
     pub fn size_label(&self, w: f64, h: f64) -> String {
         format!("W: {}\nH: {}", self.len(w), self.len(h))
     }
+    /// Star tool drag: outer (R1) and inner (R2) radii from the centre to the pointer.
+    pub fn star_radii_label(&self, outer: f64, inner: f64) -> String {
+        format!("R1: {}\nR2: {}", self.len(outer), self.len(inner))
+    }
     /// A move label: `dX: …` over `dY: …`.
     pub fn offset_label(&self, dx: f64, dy: f64) -> String {
         format!("dX: {}\ndY: {}", self.len(dx), self.len(dy))
diff --git a/crates/tools/src/shape.rs b/crates/tools/src/shape.rs
index 47ddf7a84..34553a034 100644
--- a/crates/tools/src/shape.rs
+++ b/crates/tools/src/shape.rs
@@ -308,15 +308,25 @@ impl Tool for ShapeTool {
                 cx.segment_measure_label(s, self.last)
             } else {
                 // A box's size as drawn (from its centre with Alt, square with Shift).
-                let (w, h) = match self.id {
-                    "polygon" | "star" => ((self.last - s).x.abs(), (self.last - s).y.abs()),
-                    _ => {
-                        // Along the Constrain Angle's axes, as the box is drawn (`command_at`).
-                        let (r, _) = turned_box(s, self.last, self.mods, cx.constrain_angle);
-                        (r.width(), r.height())
+                match self.id {
+                    "star" => {
+                        let outer = (self.last - s).hypot().max(0.01);
+                        // The same ratio `command_at` draws with, so the label matches the preview
+                        // (Ctrl/Cmd's held radius is already in `star_ratio`, clamped; Alt overrides it).
+                        let ratio = if self.mods.alt { straight_ratio(self.points).unwrap_or(self.star_ratio) } else { self.star_ratio };
+                        cx.star_radii_label(outer, outer * ratio)
                     }
-                };
-                cx.size_label(w, h)
+                    _ => {
+                        let (w, h) = match self.id {
+                            "polygon" => ((self.last - s).x.abs(), (self.last - s).y.abs()),
+                            _ => {
+                                let (r, _) = turned_box(s, self.last, self.mods, cx.constrain_angle);
+                                (r.width(), r.height())
+                            }
+                        };
+                        cx.size_label(w, h)
+                    }
+                }
             };
             o.push(Overlay::Measure { p, text });
         }
@@ -396,6 +406,71 @@ mod tests {
         assert!(matches!(a.last(), Some(Action::Preview(_, v)) if v["cx"] == 60.0 && v["cy"] == 60.0), "{a:?}");
     }
 
+    #[test]
+    fn star_drag_measure_label_shows_outer_and_inner_radii() {
+        let (d, _) = doc_with_rect();
+        let s = Selection::default();
+        let p = paint();
+        let cx = ToolContext { measurement_labels: true, smart_guides: false, ..cx(&d, &s, &p) };
+        let mut t = ShapeTool::new("star");
+        t.star_ratio = 0.5;
+        t.pointer(&cx, &PointerEvent::new(PointerKind::Down, 10.0, 10.0));
+        t.pointer(&cx, &PointerEvent::new(PointerKind::Drag, 50.0, 10.0));
+        let want = cx.star_radii_label(40.0, 20.0);
+        let label = t
+            .overlays(&cx)
+            .into_iter()
+            .find_map(|o| match o {
+                Overlay::Measure { text, .. } => Some(text),
+                _ => None,
+            })
+            .unwrap_or_default();
+        assert_eq!(label, want, "{label}");
+    }
+
+    /// The star label shows the radii the preview draws, also with Ctrl/Cmd + Alt and when a
+    /// Ctrl/Cmd drag shrinks the outer radius below the held inner one (the ratio is clamped).
+    #[test]
+    fn star_measure_label_matches_the_preview_with_modifiers_and_shrink() {
+        let (d, _) = doc_with_rect();
+        let s = Selection::default();
+        let p = paint();
+        let cx = ToolContext { measurement_labels: true, smart_guides: false, ..cx(&d, &s, &p) };
+        let label = |t: &ShapeTool| {
+            t.overlays(&cx)
+                .into_iter()
+                .find_map(|o| match o {
+                    Overlay::Measure { text, .. } => Some(text),
+                    _ => None,
+                })
+                .unwrap_or_default()
+        };
+        let radii = |a: &[Action]| match a.last() {
+            Some(Action::Preview(_, v)) => (v["radius1"].as_f64().unwrap(), v["radius2"].as_f64().unwrap()),
+            other => panic!("{other:?}"),
+        };
+        let cmd = Mods { cmd: true, ..Default::default() };
+        let cmd_alt = Mods { cmd: true, alt: true, ..Default::default() };
+        let mut t = ShapeTool::new("star");
+        t.star_ratio = 0.5;
+        t.pointer(&cx, &PointerEvent::new(PointerKind::Down, 10.0, 10.0));
+        t.pointer(&cx, &PointerEvent::new(PointerKind::Drag, 50.0, 10.0));
+        // Ctrl/Cmd holds the 20 inner radius while the outer one grows.
+        let a = t.pointer(&cx, &PointerEvent::new(PointerKind::Drag, 70.0, 10.0).with_mods(cmd));
+        let (r1, r2) = radii(&a);
+        assert_eq!(label(&t), cx.star_radii_label(r1, r2));
+        // Ctrl/Cmd + Alt: the preview straightens the shoulders, and so does the label.
+        let a = t.pointer(&cx, &PointerEvent::new(PointerKind::Drag, 70.0, 10.0).with_mods(cmd_alt));
+        let (r1, r2) = radii(&a);
+        assert!((r2 - 20.0).abs() > 1e-6, "Alt should override the held radius: {r2}");
+        assert_eq!(label(&t), cx.star_radii_label(r1, r2));
+        // Shrinking below the held inner radius clamps the ratio; the label follows the preview.
+        let a = t.pointer(&cx, &PointerEvent::new(PointerKind::Drag, 20.0, 10.0).with_mods(cmd));
+        let (r1, r2) = radii(&a);
+        assert!(r2 <= r1 + 1e-9, "{r1} {r2}");
+        assert_eq!(label(&t), cx.star_radii_label(r1, r2));
+    }
+
     /// During a star drag, Ctrl/Cmd keeps the inner radius while the outer one follows the pointer
     /// (the new ratio stays once the key is let go), and Alt keeps the shoulders straight (#812).
     #[test]