What Is a PSB File?

How to open, edit, & convert PSB files

A file with the PSB (Photoshop Big) file extension is an Adobe Photoshop Large Document file. The format is almost identical to Photoshop's more common PSD format except that PSB supports significantly larger files, both in image dimension and overall size.

More specifically, PSB files can be as large as 4 EB (over 4.2 billion GB) with images that have a height and width of up to 300,000 pixels. PSDs, on the other hand, are limited to 2 GB and image dimensions of 30,000 pixels.

Several PSB files used by Photoshop in Windows 10
PSB Files.

PowerDivX Subtitles files use the .PSB file extension, too. They are text files used by the PowerDivX multimedia player as a format for saving subtitles.

PSB is also an abbreviation for things not related to a file format, like PlayStation Blog, power signal box, public service broadcasting, program specification block, and polysulfide bromide battery.

How to Open a PSB File

PSB files can be opened with Adobe Photoshop.

Any text editor can open PSB subtitle files since they're just plain text files, but a program like VLC is what you need to actually run the subtitles along with a video. VLC supports not only PSB subtitles but also SRT, CDG, MPL2, SUB, UTF, VTT, and TXT. Use the Subtitle > Add Subtitle File menu to open one.

If you find that an application on your computer tries to open the PSB file but it's the wrong application or you'd rather have another installed program open PSB files, see our How to Change the Default Program for a Specific File Extension guide for making that change in Windows.

How to Convert a PSB File

Photoshop is the best way to convert a PSB file to another format. It supports saving the PSB to PSD, JPG, PNG, EPS, GIF, and several other formats.

You can also convert a PSB file without using Photoshop with a free file converter like Go2Convert. This website can convert PSB files to lots of formats, including not only those in the previous paragraph but also PDF, TGA, TIFF, and similar file formats. It should also be able to resize the PSB file before converting it.

The only downside to using an online PSB converter like Go2Convert is that the upload file size is normally limited. You also have to upload the PSB file to the website to convert it and then download it back to your computer when it's finished, both of which could take a while to complete.

Still Can't Open the File?

If your file won't open with Photoshop or a text editor, it's probably a totally different file. This might happen if you've misread the file extension, which is easy to do and will result in an unrelated file format trying to open in Photoshop.

PBS is one example. This file extension is used by PaintShop Pro Brush Strokes files, but you need Corel PaintShop Pro on your computer in order to use it. You can't open one with Photoshop even though the file extension is similar to PSB.

SPB is another that could be a Flight Simulator Mission file or a Samsung Kies Phonebook file, but neither are related to an Adobe Photoshop format.