---
title: resp.stale
summary: null
url: >-
  https://www.fastly.com/documentation/reference/vcl/variables/miscellaneous/resp-stale
---


Whether or not the response is a stale cache hit.

Stale hits are caused by asynchronous revalidation, backend failure, or an explicit `return(deliver_stale)`.

To learn more, refer to [staleness and revalidation](/guides/concepts/edge-state/cache/stale/), `resp.stale.is_error`, and `resp.stale.is_revalidating`.