A PJP file is a bitmap image created in the Progressive JPEG format (PJPEG). It contains encoded bitmap data so that the downloaded image appears progressively from a blurry picture to the final sharp image. This enables image previews to be viewed before the entire image is downloaded.

PJP images are supported by most web browsers, such as Google Chrome, Mozilla Firefox, Microsoft Edge, and Apple Safari. However, they are more often seen with the .PJPG extension. You can convert the PJP image to a .JPG image by simply renaming the .pjp file extension to .jpg then opening it with a program that supports JPG images, such as Microsoft Photos in Windows or Apple Preview in macOS. You can view the image then export it to a different image type, such as .PNG or .BMP.