diff --git a/compose/compose-file/build.md b/compose/compose-file/build.md
index aa86248a9a..c677efbaa4 100644
--- a/compose/compose-file/build.md
+++ b/compose/compose-file/build.md
@@ -350,7 +350,7 @@ the service's containers.
   service's task containers. Defaults to `source` if not specified.
 - `uid` and `gid`: The numeric UID or GID that owns the file within
   `/run/secrets/` in the service's task containers. Default value is USER running container.
-- `mode`: The [permissions](http://permissions-calculator.org/) for the file to be mounted in `/run/secrets/`
+- `mode`: The [permissions](https://chmod-calculator.com/) for the file to be mounted in `/run/secrets/`
   in the service's task containers, in octal notation.
   Default value is world-readable permissions (mode `0444`).
   The writable bit MUST be ignored if set. The executable bit MAY be set.