About JPG
JPG, or JPEG, is named after the Joint Photographic Experts Group, the committee that published the standard in 1992. It was designed for photographs at a time when a megabyte was expensive, and it solved that problem so well that it is still the default for cameras, phones and the web more than thirty years later.
Its trick is to throw away detail the eye is unlikely to miss: fine colour variation first, then the faintest textures. The quality setting controls how much goes. That makes JPG superb for photos and poor for anything with sharp edges and flat colour, such as screenshots, logos and text, where the discarded detail shows up as smudges.
What JPG cannot do
- Transparency. There is no alpha channel, so transparent areas must be filled with a colour when converting to JPG. The converter above lets you choose it.
- Animation. One frame only.
- Lossless storage. Even quality 100 loses a little, and every re-save loses more. Keep originals, and export JPGs as the last step.
JPG, JPEG, JFIF: one format
The extensions .jpg, .jpeg, .jpe and .jfif all hold the same kind of file. The three-letter version exists because early Windows limited extensions to three characters. JPEG 2000 and JPEG XL, despite the names, are completely different formats.
JPG at a glance
| First released | 1992 |
|---|---|
| Compression | Lossy |
| Transparency | No |
| Animation or pages | No |
| Best for | Photos for sharing, email and print |
| Support | Universal |
Questions people ask
What is the best quality setting for JPG?
85 to 90 for photos you want to share, 75 to 82 for web pages. Above 92 the file grows quickly for almost no visible gain.
Is JPG or PNG better?
JPG for photographs, PNG for screenshots, graphics, text and anything transparent.
Can every device open a JPG?
Practically yes. It is the most widely supported image format there is.