JPG file (Joint Photographic Experts Group)
Lossy, no transparency. Smallest files for photographs.
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Convert JPG to PNG, free and without uploading it.
What is a JPG file?
In short: A JPG file (.jpg) is an image file in the JPG format. JPG discards detail your eye is least likely to notice, then compresses what is left. It can be converted to PNG or WEBP for free in a web browser with iHateFiles, without uploading it.
Standardised in 1992 by the Joint Photographic Experts Group, the committee it is named after.
JPG discards detail your eye is least likely to notice, then compresses what is left. The quality setting decides how much it discards. It is the reason photographs on the web are measured in hundreds of kilobytes rather than tens of megabytes.
What JPG is good at
- Very small files for photographs and anything with smooth gradients
- Understood by literally everything, including hardware from the nineties
- Stores camera metadata: exposure, lens, and often the location
Where JPG falls short
- No transparency at all; transparent areas are filled in
- Each save loses a little more, and it never comes back
- Sharp edges and text pick up visible smudging around them
When to use JPG
Use JPG for photographs, and set the quality around 80: above that the file grows quickly for a difference almost nobody can see.
How to open a JPG file
Everything. It is the closest thing to a universal image format.
| Windows | Opens everywhere. |
|---|---|
| macOS | Opens everywhere. |
| Linux | Opens everywhere. |
| Phone | Opens everywhere. |
| In a browser | Every browser displays JPG. |
The thing that usually goes wrong
Re-saving a JPG repeatedly degrades it every time, because it re-encodes from the already damaged version. Edit from the original, and export to JPG once at the end.
Not sure the file really is a JPG? Identify it by its contents, whatever its extension says.
Questions
What is a JPG file?
JPG stands for Joint Photographic Experts Group. Lossy, no transparency. Smallest files for photographs. Files use the .jpg extension.
What does JPG stand for?
JPG stands for Joint Photographic Experts Group. JPG and JPEG are the same format: the three-letter extension dates from old Windows systems that allowed only three characters.
How do I open a JPG file?
On Windows: Opens everywhere. On a Mac: Opens everywhere. On a phone: Opens everywhere. Or convert a JPG here to a format that opens everywhere, free and without uploading it.
Can I convert JPG for free?
Yes. Every conversion here is free and unlimited, because your own device does the work rather than a server we have to pay for.
Is JPG lossless?
No. JPG is a lossy format, so saving discards some detail to save space.