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Image

What is a .png file?

A .png file is a Portable Network Graphics (version 1.0). This is an image format — a picture, drawing or graphic. Confusingly, this extension has been used by 4 different formats over the years — they're all listed below.

This extension has been used by more than one format

4 different formats have claimed .png over the years, so two files with the same extension aren't necessarily the same kind of thing.

How to open a .png file

  • GIMP (free) and IrfanView open a very wide range of image formats, including obsolete ones.
  • XnView MP is the best bet for unusual or legacy image types.
  • Your operating system's built-in viewer may work for mainstream formats.

The registry records this extension against Portable Network Graphics, Portable Network Graphics, Portable Network Graphics and others, so software from that family is the most likely match.

How to convert a .png file

  • Open it in GIMP or XnView and export as .png (lossless) or .jpg (smaller).

MIME type

When a .png file travels over the web, servers label it with one of these MIME types:

image/pngimage/apng

What's a MIME type?

The technical record

For archivists, developers and the merely curious: these are the PRONOM registry entries for .png.

Format nameVersionMIME typePUID
Portable Network Graphics1.0image/pngfmt/11
Portable Network Graphics1.1image/pngfmt/12
Portable Network Graphics1.2image/pngfmt/13
Animated Portable Network Graphicsimage/apngfmt/935

Got another one?