diff --git a/lib/linguist/languages.yml b/lib/linguist/languages.yml
index 6eb2a378..b1a62272 100644
--- a/lib/linguist/languages.yml
+++ b/lib/linguist/languages.yml
@@ -261,6 +261,7 @@ C++:
   - .hh
   - .hpp
   - .hxx
+  - .inl
   - .tcc
   - .tpp