Three Formats, Three Jobs
SVG, PNG, and JPEG each exist because they solve different problems. JPEG handles photographs. PNG handles graphics that need transparency or pixel-perfect accuracy. SVG handles resolution-independent vector artwork. Choosing the right format is not about which is "best" — it is about matching the format to the content.
JPEG: The Photographic Standard
JPEG uses lossy compression optimised for continuous-tone images. Photographs, landscapes, portraits, and product shots compress efficiently in JPEG because adjacent pixels share similar colours, and the human eye is forgiving of the subtle information loss.
Use JPEG for:
- Photographs and realistic images
- Hero images and backgrounds
- Any image where small quality loss is acceptable in exchange for smaller files
Avoid JPEG for:
- Text, logos, or line art — JPEG compression creates visible artefacts around sharp edges
- Images that need transparency
- Graphics that will be edited repeatedly (each save degrades quality)
PNG: Pixel-Perfect with Transparency
PNG uses lossless compression, preserving every pixel exactly. It supports full alpha transparency, making it the standard choice for logos, icons, screenshots, and UI elements overlaid on varying backgrounds.
Use PNG for:
- Logos and brand marks
- Screenshots and UI mockups
- Graphics with text overlays
- Any raster image requiring transparency
- Images with sharp edges and flat colour areas
Avoid PNG for:
- Photographs — PNG files of photos are far larger than JPEG for no visible benefit
- Icons and logos that could be represented as vectors (use SVG instead)
SVG: Scalable and Resolution-Independent
SVG is fundamentally different from JPEG and PNG. It stores images as XML-based vector instructions — shapes, paths, colours, and text — rather than a grid of pixels. This means an SVG renders perfectly at any size, from a 16-pixel favicon to a 10-metre banner.
Use SVG for:
- Logos and brand identity graphics
- Icons and icon systems
- Illustrations with flat colours and geometric shapes
- Charts, diagrams, and infographics
- Animated graphics (via CSS or JavaScript)
- Any graphic that must scale to arbitrary sizes
Avoid SVG for:
- Photographs and complex photographic imagery
- Extremely detailed illustrations with millions of paths (file size explodes)
Comparison Table
| Feature | SVG | PNG | JPEG |
|---|---|---|---|
| Type | Vector | Raster (lossless) | Raster (lossy) |
| Transparency | Yes | Yes | No |
| Scales infinitely | Yes | No | No |
| Best for photos | No | No | Yes |
| Best for logos | Yes | Acceptable | No |
| Animation | Yes (CSS/JS) | No (APNG limited) | No |
| Editable in code | Yes (XML) | No | No |
| File size for icons | Tiny | Small | Small |
| File size for photos | Huge | Large | Small |
Quick Decision Guide
- Is it a photograph? → Use JPEG (or WebP/AVIF for modern browsers)
- Is it a logo, icon, or geometric illustration? → Use SVG
- Is it a raster graphic that needs transparency? → Use PNG
- Is it a screenshot? → Use PNG
- Does it need to animate? → Use SVG (or GIF/WebP for raster animation)
Performance Considerations
For web performance, format choice interacts with file size, decode time, and caching:
- Compress PNGs with tools like pngquant or oxipng to reduce file size by 50–70 % without visible loss
- Minify SVGs with SVGO to strip unnecessary metadata and whitespace
- Use progressive JPEG encoding for large hero images so users see a preview quickly
- Consider serving WebP or AVIF versions alongside JPEG originals via the
<picture>element
Frequently Asked Questions
Can I use SVG for everything?
No. SVG is unsuitable for photographs because converting a photo to vector paths produces enormous files. SVG excels at geometric shapes, text, and illustrations — not pixel-based imagery.
Why are my PNG files so large?
PNG is lossless, so it preserves every pixel. A photo saved as PNG may be 5–10× larger than a JPEG of similar quality. For photographs, JPEG (or WebP/AVIF) is almost always the better choice.
Should I use PNG-8 or PNG-24?
PNG-8 supports up to 256 colours and is ideal for simple graphics. PNG-24 supports millions of colours and full alpha transparency. For icons with few colours, PNG-8 produces much smaller files.