diff --git a/src/utils/Resizer.ts b/src/utils/Resizer.ts
index 24668d816..9b22e7fb4 100644
--- a/src/utils/Resizer.ts
+++ b/src/utils/Resizer.ts
@@ -650,7 +650,7 @@ export default class Resizer {
    * All positioning logic
    * @return {Object}
    */
-  calc(data: Resizer) {
+  calc(data: Resizer): RectDim | undefined {
     let value;
     const opts = this.opts || {};
     const step = opts.step!;
@@ -665,7 +665,7 @@ export default class Resizer {
     const unitHeight = this.opts.unitHeight;
     const startW = unitWidth === '%' ? (startDim.w / 100) * parentW : startDim.w;
     const startH = unitHeight === '%' ? (startDim.h / 100) * parentH : startDim.h;
-    var box: RectDim = {
+    const box: RectDim = {
       t: startDim.t,
       l: startDim.l,
       w: startW,
@@ -730,6 +730,11 @@ export default class Resizer {
       box.t += startDim.h - box.h;
     }
 
+    for (const key in box) {
+      const i = key as keyof RectDim;
+      box[i] = parseInt(`${box[i]}`, 10);
+    }
+
     return box;
   }
 }