diff --git a/src/NumberInput/NumberInput.svelte b/src/NumberInput/NumberInput.svelte
index 7b8d25a4..aa85d675 100644
--- a/src/NumberInput/NumberInput.svelte
+++ b/src/NumberInput/NumberInput.svelte
@@ -191,8 +191,8 @@
         type="number"
         pattern="[0-9]*"
         aria-describedby="{errorId}"
-        data-invalid="{invalid || error}"
-        aria-invalid="{invalid || error}"
+        data-invalid="{invalid || error ? true : undefined}"
+        aria-invalid="{invalid || error ? true : undefined}"
         aria-label="{label ? undefined : ariaLabel}"
         disabled="{disabled}"
         id="{id}"