diff --git a/packages/react-core/src/components/TextArea/TextArea.tsx b/packages/react-core/src/components/TextArea/TextArea.tsx
index 267e67728a..b794fed2d7 100644
--- a/packages/react-core/src/components/TextArea/TextArea.tsx
+++ b/packages/react-core/src/components/TextArea/TextArea.tsx
@@ -60,16 +60,12 @@ class TextAreaBase extends Component<TextAreaProps> {
 
   private setAutoHeight = (field: HTMLTextAreaElement) => {
     const parent = field.parentElement;
     parent.style.setProperty('height', 'inherit');
     const computed = window.getComputedStyle(field);
     // Calculate the height
-    const height =
-      parseInt(computed.getPropertyValue('border-top-width')) +
-      parseInt(computed.getPropertyValue('padding-top')) +
-      field.scrollHeight +
-      parseInt(computed.getPropertyValue('padding-bottom')) +
-      parseInt(computed.getPropertyValue('border-bottom-width'));
+    const height = field.scrollHeight;
     parent.style.setProperty('height', `${height}px`);
+    parent.style.setProperty('box-sizing', 'content-box');
   };