diff --git a/src/library/entry.cr b/src/library/entry.cr
index 8b80d46..ceaa531 100644
--- a/src/library/entry.cr
+++ b/src/library/entry.cr
@@ -59,6 +59,7 @@ class Entry
         json.field {{str}}, @{{str.id}}
       {% end %}
         json.field "title_id", @book.id
+        json.field "sort_title", sort_title
         json.field "pages" { json.number @pages }
         unless slim
           json.field "display_name", @book.display_name @title
diff --git a/src/library/title.cr b/src/library/title.cr
index 6fa78a5..539f114 100644
--- a/src/library/title.cr
+++ b/src/library/title.cr
@@ -209,6 +209,7 @@ class Title
         json.field {{str}}, @{{str.id}}
       {% end %}
         json.field "signature" { json.number @signature }
+        json.field "sort_title", sort_title
         unless slim
           json.field "display_name", display_name
           json.field "cover_url", cover_url