diff --git a/markdown.py b/markdown.py
index b43e53ce2..e7a976084 100644
--- a/markdown.py
+++ b/markdown.py
@@ -386,7 +386,7 @@ def markdown_to_html(markdown: str) -> str:
         for hsh, hashes in titles.items():
             if line.startswith(hashes):
                 line = line.replace(hashes, '').strip()
-                line = '<' + hsh + '>' + line + '</' + hsh + '>\n'
+                line = '<' + hsh + ' id="' + line + '">' + line + '</' + hsh + '>\n'
                 ctr = -1
                 break
         html_str += line