diff --git a/doc/api/index.md b/doc/api/index.md
index 4262191327ce60..23fe9bfa039ab0 100644
--- a/doc/api/index.md
+++ b/doc/api/index.md
@@ -56,7 +56,7 @@
 * [V8](v8.html)
 * [VM](vm.html)
 * [Worker Threads](worker_threads.html)
-* [ZLIB](zlib.html)
+* [Zlib](zlib.html)
 
 <div class="line"></div>