diff --git a/docs/src/extensions.md b/docs/src/extensions.md
index 6a479ad65..10601de76 100644
--- a/docs/src/extensions.md
+++ b/docs/src/extensions.md
@@ -47,12 +47,12 @@ packages.
 
 `rm` can display a progress bar when the `-g`/`--progress` flag is set.
 
-## `hashsum`
+## `hashsum` (deprecated)
 
 This utility does not exist in GNU coreutils. `hashsum` is a utility that
 supports computing the checksums with several algorithms. The flags and options
 are identical to the `*sum` family of utils (`sha1sum`, `sha256sum`, `b2sum`,
-etc.).
+etc.). This utility will be removed in the future and it is advised to use `cksum --untagged` instead.
 
 ## `b3sum`