What Is a PSD File?

A PSD file is used mainly in Adobe Photoshop as the default format for saving data. Files with this file extension are called Adobe Photoshop Document files, and are in a proprietary format developed by Adobe.

Although some PSD files contain just one single image and nothing else, the common use for a PSD file includes much more than just storing an image file. They support multiple pictures, objects, filters, text, and more, as well as using layers, vector paths and shapes, and transparency.

For example, say you have five images within one PSD file, each on its own separate layer. Together, the pictures look as if they're on a single, flat image, but in reality, they're moveable and fully editable within their own layers — just as if you were working with separate pictures. You could reopen this PSD file as many times as you want and make changes to single layers without affecting the others.

The best programs for opening and editing PSD files are Adobe Photoshop and Adobe Photoshop Elements, as well as CorelDRAW and Corel's PaintShop Pro tool.

Other Adobe programs can use PSD files, too, like Adobe Illustrator, Adobe Premiere Pro, and Adobe After Effects. These programs, however, are mainly used for video or audio editing and not as graphics editors like Photoshop.

If you're looking for a free program to open PSD files, we recommend GIMP. It's an extremely popular, and completely free, photo editing/creation tool that will open PSD files and other file formats. You can also use GIMP to edit PSD files but could run into problems since it has issues recognizing complex layers and other advanced features that might have been used in Photoshop when the file was created.

Paint.NET (with the Paint.NET PSD Plugin) is another free program like GIMP that can open PSD files. Other free photo editors support opening PSD files as well, and some can also save to the PSD file format.

If you want to quickly open a PSD file without Photoshop, we highly recommend Photopea. It's a free online photo editor that runs in your browser that not only lets you see all the layers of the PSD, but also do some editing...although nothing like what Photoshop provides. You can also use Photopea to save files back to your computer in the PSD format.

IrfanView, PSD Viewer, and Apple's QuickTime Picture Viewer — part of their free QuickTime program — will open PSD files, too, but you can't use them to edit the PSD file. You also won't have any kind of layer support because they just act as PSD viewers.

Apple Preview, included with the macOS, should be able to open PSD files by default.

The most common reason to convert a PSD file is probably so you can use it like a regular image file, like a JPG, PNG, BMP, or GIF file, perhaps. That way you can upload the image online (many sites don't accept PSD files) or send it over email so it can be opened on computers that don't use PSD openers.

If you have Photoshop on your computer, converting a PSD file to an image file format is extremely easy: use the File > Save As... menu option.

If you don't have Photoshop, one quick way to convert a PSD file to PNG, JPEG, SVG (vector), GIF, or WEBP is through Photopea's File > Export as option.

Most of the programs from above that support editing or viewing PSD files can convert the PSD to another format using a similar process as Photoshop and Photopea.

Another option for converting PSD files is through a free image converter program.

PSD files have a maximum height and width of 30,000 pixels, as well as a maximum size of 2 GB.

A similar format to PSD is PSB (Adobe Photoshop Large Document file), which supports larger images, up to 300,000 pixels, and file sizes up to around 4 exabytes (4 billion GB).

Adobe has some advanced reading on the PSD file format in the Adobe Photoshop File Format Specification document on their site.

Keep in mind that some file extensions look similar to .PSD but have nothing to do with this image format. WPS, XSD, and PPS are a few examples. Double-check the file extension to be sure it reads .PSD before concluding that you can't open the file with the PSD programs above.