Efficient Image Formats
JPEG, WebP, AVIF and PNG – selected according to file size, transparency and compatibility.
Formats & Performance
Images often account for the largest share of a website’s data volume. The file format determines how efficiently an image is stored and delivered.
Depending on the format, the following factors vary:
- File size and loading speed
- Detail retention and compression behaviour
- Transparency for cut-outs and overlays
- Browser and system compatibility
Format selection is therefore not merely an export setting, but part of a stable web structure.
3 Criteria in Practice
Detail
JPEG is a lossy format and has proven itself for traditional photographic content. WebP and AVIF often result in significantly smaller file sizes while maintaining comparable quality.
Transparency
PNG, WebP and AVIF support transparency. This is relevant for cut-outs, UI-related imagery, overlays or hybrid layouts.
Compatibility
Not every system handles every format the same way. The CMS, online store, image CDN, and browser support determine which formats are appropriate.
Example:
File Size at 1200 px Width
At comparable visual quality, typical tendencies are:
- JPEG: approx. 250–400 KB
- WebP: approx. 150–250 KB
- AVIF: sometimes below 150 KB
- PNG: significantly larger at the same resolution
Actual values depend on the subject matter (detail, texture, edges) and compression settings. However, these comparisons illustrate how strongly format choice can influence PageSpeed and mobile loading times.
| Format | Compression | Transparency | File Size | Typical Use |
|---|---|---|---|---|
| JPEG | Lossy | No | Medium | Classic photography |
| WebP | Efficient | Yes | Small | Modern websites, CMS |
| AVIF | Highly efficient | Yes | Very small | Performance-focused projects |
| PNG | Lossless | Yes | Large | Cut-outs, graphics, UI-related imagery |
Format Selection
The appropriate format depends not only on the image itself, but on its intended use.
At Shutterwerk, format selection is therefore defined within context: website performance, system environment, transparency requirements and long-term scalability.
The result is image data that functions technically – and remains visually stable.
Contact
If you have any questions about formats, performance, or workflow, please feel free to contact us.
