him2him2 · radarhere · Feb 21, 2026 · Feb 21, 2026 · Feb 21, 2026 · Feb 21, 2026
diff --git a/Tests/test_file_gif.py b/Tests/test_file_gif.py
@@ -716,17 +716,17 @@ def test_dispose2_diff(tmp_path: Path) -> None:
     )
 
     with Image.open(out) as img:
-        for i, colours in enumerate(circles):
+        for i, colors in enumerate(circles):
             img.seek(i)
             rgb_img = img.convert("RGBA")
 
-            # Check left circle is correct colour
-            assert rgb_img.getpixel((20, 50)) == colours[0]
+            # Check left circle is correct color
+            assert rgb_img.getpixel((20, 50)) == colors[0]
 
-            # Check right circle is correct colour
-            assert rgb_img.getpixel((80, 50)) == colours[1]
+            # Check right circle is correct color
+            assert rgb_img.getpixel((80, 50)) == colors[1]
 
-            # Check BG is correct colour
+            # Check BG is correct color
             assert rgb_img.getpixel((1, 1)) == (255, 255, 255, 0)
 
 

diff --git a/Tests/test_file_tiff_metadata.py b/Tests/test_file_tiff_metadata.py
@@ -26,7 +26,7 @@ def test_rt_metadata(tmp_path: Path) -> None:
 
     img = hopper()
 
-    # Behaviour change: re #1416
+    # Behavior change: re #1416
     # Pre ifd rewrite, ImageJMetaData was being written as a string(2),
     # Post ifd rewrite, it's defined as arbitrary bytes(7). It should
     # roundtrip with the actual bytes, rather than stripped text

diff --git a/Tests/test_image_convert.py b/Tests/test_image_convert.py
@@ -336,7 +336,7 @@ def test_matrix_xyz(mode: str) -> None:
     assert im.mode == "RGB"
 
     # Act
-    # Convert an RGB image to the CIE XYZ colour space
+    # Convert an RGB image to the CIE XYZ color space
     converted_im = im.convert(mode=mode, matrix=matrix)
 
     # Assert

diff --git a/Tests/test_image_resize.py b/Tests/test_image_resize.py
@@ -167,7 +167,7 @@ def test_unknown_filter(self) -> None:
             self.resize(hopper(), (10, 10), 9)  # type: ignore[arg-type]
 
     def test_cross_platform(self, tmp_path: Path) -> None:
-        # This test is intended for only check for consistent behaviour across
+        # This test is intended for only check for consistent behavior across
         # platforms. So if a future Pillow change requires that the test file
         # be updated, that is okay.
         im = hopper().resize((64, 64))

diff --git a/Tests/test_imagedraw.py b/Tests/test_imagedraw.py
@@ -999,7 +999,7 @@ def test_floodfill(bbox: Coords) -> None:
         with Image.open(expected) as im_floodfill:
             assert_image_equal(im, im_floodfill)
 
-    # Test that using the same colour does not change the image
+    # Test that using the same color does not change the image
     ImageDraw.floodfill(im, centre_point, red)
     assert_image_equal(im, im_floodfill)
 

diff --git a/docs/handbook/image-file-formats.rst b/docs/handbook/image-file-formats.rst
@@ -122,7 +122,7 @@ BMP
 ^^^
 
 Pillow reads and writes Windows and OS/2 BMP files containing ``1``, ``L``, ``P``,
-or ``RGB`` data. 16-colour images are read as ``P`` images.
+or ``RGB`` data. 16-color images are read as ``P`` images.
 Support for reading 8-bit run-length encoding was added in Pillow 9.1.0.
 Support for reading 4-bit run-length encoding was added in Pillow 9.3.0.
 
@@ -1192,7 +1192,7 @@ TIFF
 ^^^^
 
 Pillow reads and writes TIFF files. It can read both striped and tiled
-images, pixel and plane interleaved multi-band images. If you have
+images, pixel and plane interleaved multiband images. If you have
 libtiff and its headers installed, Pillow can read and write many kinds
 of compressed TIFF files. If not, Pillow will only read and write
 uncompressed files.

diff --git a/docs/handbook/tutorial.rst b/docs/handbook/tutorial.rst
@@ -233,8 +233,8 @@ RGBA image and also using it as the mask would paste the opaque portion
 of the image but not its transparent background.
 
 The Python Imaging Library also allows you to work with the individual bands of
-a multi-band image, such as an RGB image. The split method creates a set of
-new images, each containing one band from the original multi-band image. The
+a multiband image, such as an RGB image. The split method creates a set of
+new images, each containing one band from the original multiband image. The
 merge function takes a mode and a tuple of images, and combines them into a new
 image. The following sample swaps the three bands of an RGB image:
 

diff --git a/docs/handbook/writing-your-own-image-plugin.rst b/docs/handbook/writing-your-own-image-plugin.rst
@@ -377,7 +377,7 @@ The setup function needs to call ``PyImaging_DecoderNew`` or
 
 **pulls_fd**/**pushes_fd**
   If the decoder has ``pulls_fd`` or the encoder has ``pushes_fd`` set to 1,
-  ``state->fd`` will be a pointer to the Python file like object. The codec may
+  ``state->fd`` will be a pointer to the Python file-like object. The codec may
   use the functions in ``codec_fd.c`` to read or write directly with the file
   like object rather than have the data pushed through a buffer.
 

diff --git a/docs/reference/ImageFilter.rst b/docs/reference/ImageFilter.rst
@@ -81,13 +81,13 @@ Pillow provides the following set of predefined image enhancement filters:
 
 .. class:: MultibandFilter
 
-    An abstract mixin used for filtering multi-band images
+    An abstract mixin used for filtering multiband images
     (for use with :py:meth:`~PIL.Image.Image.filter`).
 
     Implementors must provide the following method:
 
     .. method:: filter(self, image)
 
-        Applies a filter to a multi-band image.
+        Applies a filter to a multiband image.
 
         :returns: A filtered copy of the image.
diff --git a/docs/reference/ImageMath.rst b/docs/reference/ImageMath.rst
@@ -7,7 +7,7 @@
 The :py:mod:`~PIL.ImageMath` module can be used to evaluate “image expressions”, that
 can take a number of images and generate a result.
 
-:py:mod:`~PIL.ImageMath` only supports single-layer images. To process multi-band
+:py:mod:`~PIL.ImageMath` only supports single-layer images. To process multiband
 images, use the :py:meth:`~PIL.Image.Image.split` method or :py:func:`~PIL.Image.merge`
 function.
 
@@ -55,7 +55,7 @@ Example: Using the :py:mod:`~PIL.ImageMath` module
         recommended to process expressions without considering this.
         :py:meth:`lambda_eval` is a more secure alternative.
 
-    :py:mod:`~PIL.ImageMath` only supports single-layer images. To process multi-band
+    :py:mod:`~PIL.ImageMath` only supports single-layer images. To process multiband
     images, use the :py:meth:`~PIL.Image.Image.split` method or
     :py:func:`~PIL.Image.merge` function.
 

diff --git a/docs/reference/PixelAccess.rst b/docs/reference/PixelAccess.rst
@@ -59,7 +59,7 @@ Access using negative indexes is also possible. ::
 
         Modifies the pixel at x,y. The color is given as a single
         numerical value for single band images, and a tuple for
-        multi-band images. See :ref:`colors` for more information.
+        multiband images. See :ref:`colors` for more information.
 
         :param xy: The pixel coordinate, given as (x, y).
         :param color: The pixel value according to its mode,

diff --git a/docs/releasenotes/3.0.0.rst b/docs/releasenotes/3.0.0.rst
@@ -49,5 +49,5 @@ LibJpeg and Zlib are required by default
 
 The external dependencies on libjpeg and zlib are now required by default.
 If the headers or libraries are not found, then installation will abort
-with an error. This behaviour can be disabled with the ``--disable-libjpeg``
+with an error. This behavior can be disabled with the ``--disable-libjpeg``
 and ``--disable-zlib`` flags.
diff --git a/docs/releasenotes/7.2.0.rst b/docs/releasenotes/7.2.0.rst
@@ -47,7 +47,7 @@ Image._showxv
 ~~~~~~~~~~~~~
 
 ``Image._showxv`` has been deprecated. Use :py:meth:`~PIL.Image.Image.show`
-instead. If custom behaviour is required, use :py:meth:`~PIL.ImageShow.register` to add
+instead. If custom behavior is required, use :py:meth:`~PIL.ImageShow.register` to add
 a custom :py:class:`~PIL.ImageShow.Viewer` class.
 
 ImageFile.raise_ioerror

diff --git a/docs/releasenotes/8.2.0.rst b/docs/releasenotes/8.2.0.rst
@@ -140,7 +140,7 @@ create a circle, but not any other ellipse. ::
 ImageOps.autocontrast: preserve_tone
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-The default behaviour of :py:meth:`~PIL.ImageOps.autocontrast` is to normalize
+The default behavior of :py:meth:`~PIL.ImageOps.autocontrast` is to normalize
 separate histograms for each color channel, changing the tone of the image. The new
 ``preserve_tone`` argument keeps the tone unchanged by using one luminance histogram
 for all channels.
@@ -154,7 +154,7 @@ be registered. It uses GraphicsMagick_, an ImageMagick_ fork, to display images.
 The GraphicsMagick based viewer has a lower priority than its ImageMagick
 counterpart.  Thus, if both ImageMagick and GraphicsMagick are installed,
 ``im.show()`` and :py:func:`.ImageShow.show()` prefer the viewer based on
-ImageMagick, i.e the behaviour stays the same for Pillow users having
+ImageMagick, i.e the behavior stays the same for Pillow users having
 ImageMagick installed.
 
 ImageShow.IPythonViewer
@@ -166,7 +166,7 @@ to users of Google Colab, allowing ``im.show()`` to display images.
 
 It is lower in priority than the other default :py:class:`PIL.ImageShow.Viewer`
 instances, so it will only be used by ``im.show()`` or :py:func:`.ImageShow.show()`
-if none of the other viewers are available. This means that the behaviour of
+if none of the other viewers are available. This means that the behavior of
 :py:class:`PIL.ImageShow` will stay the same for most Pillow users.
 
 Saving TIFF with ICC profile

diff --git a/docs/releasenotes/9.0.0.rst b/docs/releasenotes/9.0.0.rst
@@ -92,7 +92,7 @@ Image._showxv
 ^^^^^^^^^^^^^
 
 ``Image._showxv`` has been removed. Use :py:meth:`~PIL.Image.Image.show`
-instead. If custom behaviour is required, use :py:meth:`~PIL.ImageShow.register` to add
+instead. If custom behavior is required, use :py:meth:`~PIL.ImageShow.register` to add
 a custom :py:class:`~PIL.ImageShow.Viewer` class.
 
 ImageFile.raise_ioerror

diff --git a/docs/releasenotes/9.1.0.rst b/docs/releasenotes/9.1.0.rst
@@ -181,7 +181,7 @@ GifImagePlugin loading strategy
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 Pillow 9.0.0 introduced the conversion of subsequent GIF frames to ``RGB`` or ``RGBA``. This
-behaviour can now be changed so that the first ``P`` frame is converted to ``RGB`` as
+behavior can now be changed so that the first ``P`` frame is converted to ``RGB`` as
 well. ::
 
     from PIL import GifImagePlugin

diff --git a/docs/releasenotes/9.3.0.rst b/docs/releasenotes/9.3.0.rst
@@ -8,7 +8,7 @@ Initialize libtiff buffer when saving
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 When saving a TIFF image to a file object using libtiff, the buffer was not
-initialized. This behaviour introduced in Pillow 2.0.0, and has now been fixed.
+initialized. This behavior introduced in Pillow 2.0.0, and has now been fixed.
 
 Decode JPEG compressed BLP1 data in original mode
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

diff --git a/src/PIL/FpxImagePlugin.py b/src/PIL/FpxImagePlugin.py
@@ -21,7 +21,7 @@
 from . import Image, ImageFile
 from ._binary import i32le as i32
 
-# we map from colour field tuples to (mode, rawmode) descriptors
+# we map from color field tuples to (mode, rawmode) descriptors
 MODES = {
     # opacity
     (0x00007FFE,): ("A", "L"),

diff --git a/src/PIL/GifImagePlugin.py b/src/PIL/GifImagePlugin.py
@@ -8,7 +8,7 @@
 # 1995-09-01 fl   Created
 # 1996-12-14 fl   Added interlace support
 # 1996-12-30 fl   Added animation support
-# 1997-01-05 fl   Added write support, fixed local colour map bug
+# 1997-01-05 fl   Added write support, fixed local color map bug
 # 1997-02-23 fl   Make sure to load raster data in getdata()
 # 1997-07-05 fl   Support external decoder (0.4)
 # 1998-07-09 fl   Handle all modes when saving (0.5)
@@ -115,7 +115,7 @@ def _open(self) -> None:
         if flags & 128:
             # get global palette
             self.info["background"] = s[11]
-            # check if palette contains colour indices
+            # check if palette contains color indices
             p = self.fp.read(3 << bits)
             if self._is_palette_needed(p):
                 palette = ImagePalette.raw("RGB", p)
@@ -366,7 +366,7 @@ def _rgb(color: int) -> tuple[int, int, int]:
         if self.dispose_extent and self.disposal_method >= 2:
             try:
                 if self.disposal_method == 2:
-                    # replace with background colour
+                    # replace with background color
 
                     # only dispose the extent in this frame
                     x0, y0, x1, y1 = self.dispose_extent

diff --git a/src/PIL/Image.py b/src/PIL/Image.py
@@ -1569,7 +1569,7 @@ def getextrema(self) -> tuple[float, float] | tuple[tuple[int, int], ...]:
         the image.
 
         :returns: For a single-band image, a 2-tuple containing the
-           minimum and maximum pixel value.  For a multi-band image,
+           minimum and maximum pixel value.  For a multiband image,
            a tuple containing one 2-tuple for each band.
         """
 
@@ -2174,7 +2174,7 @@ def putpixel(
         """
         Modifies the pixel at the given position. The color is given as
         a single numerical value for single-band images, and a tuple for
-        multi-band images. In addition to this, RGB and RGBA tuples are
+        multiband images. In addition to this, RGB and RGBA tuples are
         accepted for P and PA images. See :ref:`colors` for more information.
 
         Note that this method is relatively slow.  For more extensive changes,
@@ -2474,7 +2474,7 @@ def rotate(
         copy of this image, rotated the given number of degrees counter
         clockwise around its centre.
 
-        :param angle: In degrees counter clockwise.
+        :param angle: In degrees counter-clockwise.
         :param resample: An optional resampling filter.  This can be
            one of :py:data:`Resampling.NEAREST` (use nearest neighbour),
            :py:data:`Resampling.BILINEAR` (linear interpolation in a 2x2
@@ -2745,7 +2745,7 @@ def show(self, title: str | None = None) -> None:
         Displays this image. This method is mainly intended for debugging purposes.
 
         This method calls :py:func:`PIL.ImageShow.show` internally. You can use
-        :py:func:`PIL.ImageShow.register` to override its default behaviour.
+        :py:func:`PIL.ImageShow.register` to override its default behavior.
 
         The image is first saved to a temporary file. By default, it will be in
         PNG format.
@@ -3193,7 +3193,7 @@ def new(
     :param size: A 2-tuple, containing (width, height) in pixels.
     :param color: What color to use for the image. Default is black. If given,
        this should be a single integer or floating point value for single-band
-       modes, and a tuple for multi-band modes (one value per band). When
+       modes, and a tuple for multiband modes (one value per band). When
        creating RGB or HSV images, you can also use color strings as supported
        by the ImageColor module. See :ref:`colors` for more information. If the
        color is None, the image is not initialised.

diff --git a/src/PIL/ImageCms.py b/src/PIL/ImageCms.py
@@ -230,7 +230,7 @@ class ImageCmsProfile:
     def __init__(self, profile: str | SupportsRead[bytes] | core.CmsProfile) -> None:
         """
         :param profile: Either a string representing a filename,
-            a file like object containing a profile or a
+            a file-like object containing a profile or a
             low-level profile object
 
         """

diff --git a/src/PIL/ImageColor.py b/src/PIL/ImageColor.py
@@ -2,7 +2,7 @@
 # The Python Imaging Library
 # $Id$
 #
-# map CSS3-style colour description strings to RGB
+# map CSS3-style color description strings to RGB
 #
 # History:
 # 2002-10-24 fl   Added support for CSS-style color strings
@@ -166,9 +166,9 @@ def getcolor(color: str, mode: str) -> int | tuple[int, ...]:
 
 
 colormap: dict[str, str | tuple[int, int, int]] = {
-    # X11 colour table from https://drafts.csswg.org/css-color-4/, with
+    # X11 color table from https://drafts.csswg.org/css-color-4/, with
     # gray/grey spelling issues fixed.  This is a superset of HTML 4.0
-    # colour names used in CSS 1.
+    # color names used in CSS 1.
     "aliceblue": "#f0f8ff",
     "antiquewhite": "#faebd7",
     "aqua": "#00ffff",

diff --git a/src/PIL/ImageEnhance.py b/src/PIL/ImageEnhance.py
@@ -43,8 +43,8 @@ def enhance(self, factor: float) -> Image.Image:
 class Color(_Enhance):
     """Adjust image color balance.
 
-    This class can be used to adjust the colour balance of an image, in
-    a manner similar to the controls on a colour TV set. An enhancement
+    This class can be used to adjust the color balance of an image, in
+    a manner similar to the controls on a color TV set. An enhancement
     factor of 0.0 gives a black and white image. A factor of 1.0 gives
     the original image.
     """

diff --git a/src/PIL/ImageFile.py b/src/PIL/ImageFile.py
@@ -48,7 +48,7 @@
 MAXBLOCK = 65536
 """
 By default, Pillow processes image data in blocks. This helps to prevent excessive use
-of resources. Codecs may disable this behaviour with ``_pulls_fd`` or ``_pushes_fd``.
+of resources. Codecs may disable this behavior with ``_pulls_fd`` or ``_pushes_fd``.
 
 When reading an image, this is the number of bytes to read at once.
 

diff --git a/src/PIL/ImageMath.py b/src/PIL/ImageMath.py
@@ -240,7 +240,7 @@ def lambda_eval(expression: Callable[[dict[str, Any]], Any], **kw: Any) -> Any:
     """
     Returns the result of an image function.
 
-    :py:mod:`~PIL.ImageMath` only supports single-layer images. To process multi-band
+    :py:mod:`~PIL.ImageMath` only supports single-layer images. To process multiband
     images, use the :py:meth:`~PIL.Image.Image.split` method or
     :py:func:`~PIL.Image.merge` function.
 
@@ -271,7 +271,7 @@ def unsafe_eval(expression: str, **kw: Any) -> Any:
     recommended to process expressions without considering this.
     :py:meth:`~lambda_eval` is a more secure alternative.
 
-    :py:mod:`~PIL.ImageMath` only supports single-layer images. To process multi-band
+    :py:mod:`~PIL.ImageMath` only supports single-layer images. To process multiband
     images, use the :py:meth:`~PIL.Image.Image.split` method or
     :py:func:`~PIL.Image.merge` function.
 

diff --git a/src/PIL/ImageTk.py b/src/PIL/ImageTk.py
@@ -201,7 +201,7 @@ class BitmapImage:
     transparent.  Options, if any, are passed on to Tkinter.  The most commonly
     used option is ``foreground``, which is used to specify the color for the
     non-transparent parts.  See the Tkinter documentation for information on
-    how to specify colours.
+    how to specify colors.
 
     :param image: A PIL image.
     """

diff --git a/src/PIL/ImageWin.py b/src/PIL/ImageWin.py
@@ -56,7 +56,7 @@ class Dib:
 
     If the display requires a palette, this constructor creates a suitable
     palette and associates it with the image. For an "L" image, 128 graylevels
-    are allocated. For an "RGB" image, a 6x6x6 colour cube is used, together
+    are allocated. For an "RGB" image, a 6x6x6 color cube is used, together
     with 20 graylevels.
 
     To make sure that palettes work properly under Windows, you must call the

diff --git a/src/PIL/JpegImagePlugin.py b/src/PIL/JpegImagePlugin.py
@@ -188,7 +188,7 @@ def COM(self: JpegImageFile, marker: int) -> None:
 def SOF(self: JpegImageFile, marker: int) -> None:
     #
     # Start of frame marker.  Defines the size and mode of the
-    # image.  JPEG is colour blind, so we use some simple
+    # image.  JPEG is color blind, so we use some simple
     # heuristics to map the number of layers to an appropriate
     # mode.  Note that this could be made a bit brighter, by
     # looking for JFIF and Adobe APP markers.

diff --git a/src/PIL/PcxImagePlugin.py b/src/PIL/PcxImagePlugin.py
@@ -204,7 +204,7 @@ def _save(im: Image.Image, fp: IO[bytes], filename: str | bytes) -> None:
     )
 
     if im.mode == "P":
-        # colour palette
+        # color palette
         fp.write(o8(12))
         palette = im.im.getpalette("RGB", "RGB")
         palette += b"\x00" * (768 - len(palette))