diff --git a/man/zx.1 b/man/zx.1
index dd3b124ee8d..eb30e359336 100644
--- a/man/zx.1
+++ b/man/zx.1
@@ -21,6 +21,8 @@ prefix all commands
 postfix all commands
 .SS --eval=<js>, -e
 evaluate script
+.SS --ext=<.mjs>
+default extension
 .SS --install, -i
 install dependencies
 .SS --repl
diff --git a/src/cli.ts b/src/cli.ts
index 77f66f8b936..b3edaaddbe4 100644
--- a/src/cli.ts
+++ b/src/cli.ts
@@ -58,7 +58,7 @@ export function printUsage() {
    --postfix=<command>  postfix all commands
    --cwd=<path>         set current directory
    --eval=<js>, -e      evaluate script 
-   --ext=<.mjs>         eval extension
+   --ext=<.mjs>         default extension
    --install, -i        install dependencies
    --version, -v        print current zx version
    --help, -h           print help