diff --git a/pydu/convert.pyi b/pydu/convert.pyi
new file mode 100644
index 0000000..256bd09
--- /dev/null
+++ b/pydu/convert.pyi
@@ -0,0 +1,16 @@
+from typing import Any
+
+
+def boolean(obj: Any) -> bool: ...
+def bin2oct(x: str) -> str: ...
+def bin2dec(x: str) -> int: ...
+def bin2hex(x: str) -> str: ...
+def oct2bin(x: str) -> str: ...
+def oct2dec(x: str) -> int: ...
+def oct2hex(x: str) -> str: ...
+def dec2bin(x: int) -> str: ...
+def dec2oct(x: int) -> str: ...
+def dec2hex(x: int) -> str: ...
+def hex2bin(x: str) -> str: ...
+def hex2oct(x: str) -> str: ...
+def hex2dec(x: str) -> int: ...