The Short Answer
Need a transparent background or lossless text? Choose PNG. Working with photos, scans, or large web images? Choose JPG. For websites and mobile, prefer WebP — it works in all modern browsers and delivers the smallest file size.
Format Comparison at a Glance
| Dimension | PNG | JPG / JPEG | WebP |
|---|---|---|---|
| Compression | Lossless | Lossy | Lossy or lossless |
| Transparency | Supported | Not supported | Supported |
| Photo quality | Large files | Small files, great quality | Usually 25%–35% smaller |
| Text / icons / screenshots | Crisp edges | Prone to artifacts | Also crisp in lossless mode |
| Animation | Not supported | Not supported | Supported (animated WebP) |
| Browser support | Universal | Universal | Native in modern browsers, fallback needed for older ones |
| Typical use cases | Logos, transparent assets, contract screenshots | Camera photos, scans | Web images, mobile covers |
How to Choose: Decision by Scenario
- Logos / icons / assets with transparent backgrounds → PNG or WebP (transparency + lossless).
- Camera photos / portraits / scans → JPG at quality 0.85–0.92 offers the best balance.
- Hero images / thumbnails → WebP for the smallest file size; provide a JPG fallback for older browsers if needed.
- Screenshots with lots of text → PNG, to avoid color noise from lossy compression.
Conversion and Compression Tips
- For batch conversion between formats (JPG ↔ PNG ↔ WebP), use the image batch converter to process many files at once.
- When you need to balance file size against quality for the same image, use the image compressor to tune quality and dimensions directly.
- When you need a transparent background, cut out the subject with the background remover first, then export as PNG.
Frequently Asked Questions (FAQ)
WebP won't open in WeChat or old browsers — what should I do?
All modern mainstream browsers and WeChat now support WebP; if compatibility is critical, export JPG instead or keep PNG as a fallback.
Why does the background turn black after converting PNG to JPG?
JPG doesn't support transparency, so transparent areas are filled with black. Flatten the image onto a white background or composite it onto the target background before converting.
Which format uses the least bandwidth for web images?
At the same visual quality, WebP is usually the smallest, followed by JPG, with PNG the largest. For photo-heavy content, prefer WebP or JPG.
References
- WebP — Google Developers: https://developers.google.com/speed/webp
- PNG — W3C: https://www.w3.org/TR/png-3/
- JPEG — Wikipedia: https://en.wikipedia.org/wiki/JPEG