JPG / JPEG Image Format
Joint Photographic Experts Group
What is JPG?
JPG, also known as JPEG, is one of the most widely used image formats. It is particularly useful for photographs and other images where a smaller file size is more important than perfect pixel-level quality.
When to use JPG
- Photographs and natural scenes
- Web images where file size matters
- Images without transparency
- When wide compatibility is needed (all devices and browsers)
Advantages
- Very small file sizes for photographs
- Universally supported — every browser, camera, and device
- Adjustable quality/compression level
- Fast to encode and decode
Disadvantages
- Lossy compression — quality is lost each time the image is saved
- No transparency support
- Artifacts visible at high compression around text and sharp edges
- Not suitable for logos, screenshots, or line art
Transparency
JPG does not support transparency. When a PNG with transparency is converted to JPG, transparent areas are filled with a solid background color (typically white).
JPG vs other formats
JPG vs PNG: JPG is smaller for photographs but lossy and lacks transparency. PNG is lossless with transparency but larger.
JPG vs WebP: WebP produces 25-35% smaller files at equivalent quality while also supporting transparency.
JPG vs AVIF: AVIF can be 50% smaller than JPG at similar visual quality, but encoding is slower.