diff --git a/src/js/game/camera.js b/src/js/game/camera.js
index cd290b5a..66d7efa8 100644
--- a/src/js/game/camera.js
+++ b/src/js/game/camera.js
@@ -502,10 +502,10 @@ export class Camera extends BasicSerializableObject {
         }
         const prevZoom = this.zoomLevel;
 
-        const scale = 1 + 0.15 * this.root.app.settings.getScrollWheelSensitivity();
+        const delta = Math.sign(event.deltaY) * -0.15 * this.root.app.settings.getScrollWheelSensitivity();
         assert(Number.isFinite(delta), "Got invalid delta in mouse wheel event: " + event.deltaY);
         assert(Number.isFinite(this.zoomLevel), "Got invalid zoom level *before* wheel: " + this.zoomLevel);
-        this.zoomLevel *= (event.deltaY < 0) ? scale : 1/scale;
+        this.zoomLevel *= 1 + delta;
         assert(Number.isFinite(this.zoomLevel), "Got invalid zoom level *after* wheel: " + this.zoomLevel);
 
         this.clampZoomLevel();