diff --git a/assets/mixer.html b/assets/mixer.html
index b797de1..b6ef14a 100644
--- a/assets/mixer.html
+++ b/assets/mixer.html
@@ -3,7 +3,7 @@
 <h1><img alt=Logo src='{{.pathPrefix}}/assets/icon-180.png'> Mixer &mdash; <a href="/{{.pathPrefix}}">Httpbun</a></h1>
 
 <p style="font-size:1.2em">Build your own API endpoint, by combining multiple functionalities into one endpoint.
-<a href="help/mixer" style="white-space:nowrap">User guide</a>.</p>
+<a href="{{.pathPrefix}}/help/mixer" style="white-space:nowrap">User guide</a>.</p>
 
 <noscript><p style="color:red">This page requires JavaScript. Please enable it.</p></noscript>