3 file types use the .pxd file extension.

What is a PXD file?

A PXD file is an image file created by Pixelmator Pro, a professional image-editing program. It is the native format for saving images in Pixelmator Pro and includes image layers, adjustments, effects, and other edits made to the image. Only Pixelmator Pro can open PXD files; Pixelmator Classic and Pixelmator for iOS do not support the format.

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How to open a PXD file

How to convert a PXD file

Category: Raster Image Files

Pixlr Layered Image

A PXD file may also be a layer-based image created by the Pixlr X or Pixlr E image editors. It contains some combination of image, text, adjustment, filter, and mask layers. PXD files are similar to the .PSD files used by Adobe Photoshop but can be opened only in Pixlr.

Pixlr is a primarily web-based suite of image editing applications that graphic designers and photographers use to create and edit images. Pixlr is similar to Adobe Photoshop, except that Pixlr's web version functions entirely within a user's web browser.

If a user wanted to save an in-progress Pixlr editing project to their PC or mobile device, they could previously save the project as a PXD file. PXD files preserve the layer-based edits a user has made to an image, so the user can continue to adjust the image's layers as needed. In contrast, saving a Pixlr image as a .JPG , .PNG , or .WEBP file flattens the image to a single layer.

In 2021, the .PXZ file format replaced the PXD file format, and Pixlr began saving users' projects as PXZ files. However, Pixlr users can still open previously-created PXD files in Pixlr.

NOTE: Autodesk acquired Pixlr in 2011, then Inmagine acquired Pixlr from Autodesk in 2017.

You can open a PXD file in Pixlr X or Pixlr E (Web, Windows, Mac). To open a PXD file in the web version of Pixlr X or Pixlr E:

Programs that open PXD files

Updated: June 18, 2021

Pyrex Definition File

A PXD file may also be a definition file used by Pyrex or Cython, which are programming languages designed to create Python modules with performance improvements using C-like code. It contains declarations for classes , functions , constants , or variables that can be shared across multiple modules. PXD files are similar to header files in the C programming language, serving a similar purpose and allowing developers to organize and reuse code more efficiently.

Pyrex is a programming language created by Greg Ewing in the early 2000s to make it easier for developers to write Python extension modules. However, as the Python community's needs grew, Pyrex's limitations became more apparent. Cython emerged as an actively developed fork of Pyrex, offering more features, better performance, and broader compatibility with Python and C standards.

Cython is widely used in scientific computing, machine learning, and systems programming, and it supports both .PYX source files (with Python-like syntax ) and PXD definition files (for declarations). While Pyrex laid the foundation, Cython has since become the dominant tool in this space.

Developers use the cimport statement in a PYX file to include a PXD file, enabling access to the declared elements within. This structure helps manage large projects by separating definitions from implementation and improving module interoperability.

You can open PXD files with any source code or text editor. Several options include Microsoft Notepad (Windows), Apple TextEdit , and Microsoft Visual Studio Code (cross-platform).

Programs that open or reference PXD files

Updated: May 7, 2025