diff --git a/bin/dependo b/bin/dependo
index 4682606..5bc4de0 100755
--- a/bin/dependo
+++ b/bin/dependo
@@ -16,6 +16,7 @@ Commander
     .option('-x, --exclude <regex>', 'a regular expression for excluding modules')
     .option('-t, --title <title>', 'the title of the generated document (dependo)')
     .option('-v, --reverse', 'reverse direction of arrows', false)
+    .option('-e, --extensions <extensions>', 'Valid file extensions used to find files in directories e.g. .js,.ts Default: .js', '.js')
     .parse(process.argv);
 
 if (!Commander.args.length) {
@@ -35,7 +36,8 @@ var dependo = new Dependo(src, {
     exclude: Commander.exclude,
     directDeps: directDeps,
     title: Commander.title,
-    transform: Commander.reverse ? converse : undefined
+    transform: Commander.reverse ? converse : undefined,
+    extensions: Commander.extensions.split(',')
 });
 
 var html = dependo.generateHtml();
diff --git a/readme.md b/readme.md
index 12beb40..f3dd7d8 100644
--- a/readme.md
+++ b/readme.md
@@ -53,6 +53,7 @@ Options
     'requireConfig': Path to RequireJS config used to find shim dependencies and path aliases. Not used by default.
     'reverse': Reverse dependency arrow directions.
     'title': The title of the generated HTML document.
+    'extensions': Valid file extensions used to find files in directories e.g. .js,.ts Default: .js
 }
 ```
 
@@ -92,6 +93,7 @@ CLI
       -x, --exclude <regex>  a regular expression for excluding modules
       -t, --title <title>    the title of the generated document (dependo)
       -v, --reverse          reverse direction of arrows
+      -e, --extensions       file extensions to use separated by comma
 
 ### Generate HTML report of all module dependencies (AMD), and save it to /example/report.html