diff --git a/graphify/detect.py b/graphify/detect.py
index 1adad00bb..332bb5b7e 100644
--- a/graphify/detect.py
+++ b/graphify/detect.py
@@ -42,7 +42,7 @@ class FileType(str, Enum):
 _MTIME_SUBSECOND_S = 0.05
 
 CODE_EXTENSIONS = {'.py', '.ts', '.tsx', '.mts', '.cts', '.js', '.jsx', '.mjs', '.cjs', '.ejs', '.ets', '.go', '.rs', '.java', '.groovy', '.gradle', '.cpp', '.cc', '.cxx', '.c', '.h', '.hpp', '.cu', '.cuh', '.metal', '.rb', '.rake', '.swift', '.kt', '.kts', '.cs', '.scala', '.php', '.lua', '.luau', '.toc', '.zig', '.ps1', '.psm1', '.psd1', '.ex', '.exs', '.m', '.mm', '.ml', '.mli', '.jl', '.vue', '.svelte', '.astro', '.dart', '.v', '.sv', '.svh', '.sql', '.r', '.f', '.F', '.f90', '.F90', '.f95', '.F95', '.f03', '.F03', '.f08', '.F08', '.pas', '.pp', '.dpr', '.dpk', '.lpr', '.inc', '.dfm', '.lfm', '.lpk', '.sh', '.bash', '.json', '.tf', '.tfvars', '.hcl', '.dm', '.dme', '.dmi', '.dmm', '.dmf', '.sln', '.slnx', '.csproj', '.fsproj', '.vbproj', '.xaml', '.razor', '.cshtml', '.cls', '.trigger', '.lisp', '.cl', '.lsp', '.asd', '.robot', '.resource'}
-DOC_EXTENSIONS = {'.md', '.mdx', '.qmd', '.skill', '.txt', '.rst', '.html', '.yaml', '.yml'}
+DOC_EXTENSIONS = {'.md', '.mdx', '.qmd', '.skill', '.txt', '.rst', '.html', '.yaml', '.yml', '.j2', '.jinja', '.jinja2'}
 PAPER_EXTENSIONS = {'.pdf'}
 IMAGE_EXTENSIONS = {'.png', '.jpg', '.jpeg', '.gif', '.webp', '.svg'}
 OFFICE_EXTENSIONS = {'.docx', '.xlsx'}
diff --git a/tests/test_detect_jinja.py b/tests/test_detect_jinja.py
new file mode 100644
index 000000000..55ae4b874
--- /dev/null
+++ b/tests/test_detect_jinja.py
@@ -0,0 +1,6 @@
+from graphify.detect import DOC_EXTENSIONS
+
+def test_jinja2_extensions_are_documents():
+    assert '.j2' in DOC_EXTENSIONS
+    assert '.jinja' in DOC_EXTENSIONS
+    assert '.jinja2' in DOC_EXTENSIONS