diff --git a/lib/matplotlib/category.pyi b/lib/matplotlib/category.pyi
new file mode 100644
index 000000000000..e2cc0005fe19
--- /dev/null
+++ b/lib/matplotlib/category.pyi
@@ -0,0 +1,58 @@
+"""
+Plotting of string "category" data: ``plot(['d', 'f', 'a'], [1, 2, 3])`` will
+plot three points with x-axis values of 'd', 'f', 'a'.
+
+See :doc:`/gallery/lines_bars_and_markers/categorical_variables` for an
+example.
+
+The module uses Matplotlib's `matplotlib.units` mechanism to convert from
+strings to integers and provides a tick locator, a tick formatter, and the
+`.UnitData` class that creates and stores the string-to-integer mapping.
+"""
+
+from __future__ import annotations
+from matplotlib.units import ConversionInterface, AxisInfo
+from matplotlib import ticker
+from matplotlib.axis import Axis
+from collections import OrderedDict
+import numpy as np
+from typing import Any, Dict, Iterable, List, Optional, Union
+
+class StrCategoryConverter(ConversionInterface):
+    @staticmethod
+    def convert(
+        value: Union[str, Iterable[str]], 
+        unit: UnitData, 
+        axis: Axis
+    ) -> Union[float, np.ndarray]: ...
+    @staticmethod
+    def axisinfo(unit: UnitData, axis: Axis) -> AxisInfo: ...
+    @staticmethod
+    def default_units(
+        data: Union[str, Iterable[str]], 
+        axis: Axis
+    ) -> UnitData: ...
+    @staticmethod
+    def _validate_unit(unit: UnitData) -> None: ...
+
+class StrCategoryLocator(ticker.Locator):
+    def __init__(self, units_mapping: Dict[str, int]) -> None: ...
+    def __call__(self) -> List[int]: ...
+    def tick_values(self, vmin: Any, vmax: Any) -> List[int]: ...
+
+class StrCategoryFormatter(ticker.Formatter):
+    def __init__(self, units_mapping: Dict[str, int]) -> None: ...
+    def __call__(self, x: float, pos: Optional[int] = None) -> str: ...
+    def format_ticks(self, values: Iterable[float]) -> List[str]: ...
+    @staticmethod
+    def _text(value: Union[str, bytes]) -> str: ...
+
+class UnitData:
+    _mapping: OrderedDict[Union[str, bytes], int]
+    def __init__(
+        self, 
+        data: Optional[Iterable[Union[str, bytes]]] = None
+    ) -> None: ...
+    def update(self, data: Iterable[Union[str, bytes]]) -> None: ...
+    @staticmethod
+    def _str_is_convertible(val: Union[str, bytes]) -> bool: ...