diff --git a/README.md b/README.md
index a615b0c..7466543 100644
--- a/README.md
+++ b/README.md
@@ -67,7 +67,8 @@ fn main() {
 - `set_mouse_capture(bool)` – Cursor einsperren + verstecken (`CursorMode::Disabled`),
   liefert unbegrenzte Bewegungsdeltas. Impliziert `mouse_visible = false`.
 - `mouse_delta() -> (f32, f32)` – akkumulierte Mausbewegung seit dem letzten Aufruf
-  in Window-Pixeln, danach genullt. Nützlich für FPS-Kamerasteuerung.
+  in Framebuffer-Pixeln (gleiche Skala wie `MouseMove`), danach genullt. Nützlich
+  für FPS-Kamerasteuerung.
 
 ### Cursor-Modi
 
diff --git a/src/lib.rs b/src/lib.rs
index c5ab6e3..1273b33 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -255,8 +255,9 @@ impl Platform {
         self.window.set_cursor_mode(mode);
     }
 
-    /// Akkumulierte Mausbewegung seit dem letzten Aufruf, in Window-Pixeln.
-    /// Bei `set_mouse_capture(true)` liefert GLFW unbegrenzte Deltas (FPS-Stil).
+    /// Akkumulierte Mausbewegung seit dem letzten Aufruf, in Framebuffer-Pixeln
+    /// (gleiche Skala wie `Event::MouseMove`). Bei `set_mouse_capture(true)`
+    /// liefert GLFW unbegrenzte Deltas (FPS-Stil).
     pub fn mouse_delta(&mut self) -> (f32, f32) {
         std::mem::replace(&mut self.mouse_delta, (0.0, 0.0))
     }
@@ -357,16 +358,19 @@ impl Platform {
             }
             W::Char(c) => self.event_queue.push_back(Event::Char(c)),
             W::CursorPos(x, y) => {
+                let (cx, cy, cw, ch) = self.content_rect;
+                let (fw, fh) = self.framebuffer_size;
+                let sx = fw as f64 / cw as f64;
+                let sy = fh as f64 / ch as f64;
+
                 if let Some((lx, ly)) = self.last_cursor_pos {
-                    self.mouse_delta.0 += (x - lx) as f32;
-                    self.mouse_delta.1 += (y - ly) as f32;
+                    self.mouse_delta.0 += ((x - lx) * sx) as f32;
+                    self.mouse_delta.1 += ((y - ly) * sy) as f32;
                 }
                 self.last_cursor_pos = Some((x, y));
 
-                let (cx, cy, cw, ch) = self.content_rect;
-                let (fw, fh) = self.framebuffer_size;
-                let fx = ((x - cx as f64) / cw as f64 * fw as f64) as f32;
-                let fy = ((y - cy as f64) / ch as f64 * fh as f64) as f32;
+                let fx = ((x - cx as f64) * sx) as f32;
+                let fy = ((y - cy as f64) * sy) as f32;
                 self.event_queue.push_back(Event::MouseMove { x: fx, y: fy });
             }
             W::MouseButton(btn, action, _) => if let Some(button) = from_glfw_button(btn) {