How does SVG differ from raster images?
The main difference between SVG and raster images (JPG, PNG, WebP): it is in how the data is stored and displayed: vector graphics (SVG) are described with mathematical formulas, while raster ones: with a set of pixels.
All the key pros and cons follow from this difference.
1. Storage principle
| Image type | How it is structured |
|---|---|
| SVG (vector) | Made of formulas and coordinates: "draw a circle with radius 40 at point (50,50)" |
| Raster (JPG, PNG, WebP) | Made of pixels: millions of small colored dots stored in memory |
Example of SVG code for a circle:
<svg width="100" height="100">
<circle cx="50" cy="50" r="40" fill="tomato" />
</svg>In JPG, that same picture is thousands of bytes of encoded pixels.
2. Scaling (the key difference)
| Criterion | SVG | Raster |
|---|---|---|
| When enlarged | No quality loss: formulas are recalculated | Loses sharpness: becomes "pixelated" |
| Best suited for | Logos, icons, interfaces, charts | Photos, realistic images, textures |
SVG scales perfectly: on a Retina screen or an 8K monitor it stays crystal clear. A raster photo becomes "blurry" when enlarged.
3. Size and performance
| Parameter | SVG | Raster |
|---|---|---|
| File size | Very small (text-based code) | Can be heavy (up to megabytes) |
| Compression | Can be minified, gzips extremely well | Already compressed (JPG/WebP) |
| Rendering | Fast, as long as the image is simple | Fast, but fixed |
| With complex graphics | Many elements → higher CPU load | Fixed file → simpler to render |
For a logo, SVG is better, for a photo: JPG or WebP.
4. Capabilities and flexibility
| Capability | SVG | Raster |
|---|---|---|
| Scales without loss | Yes | No |
| Can be styled with CSS | Yes | No |
| Animated via CSS/JS | Yes | No |
| Interactivity (clicks, hover) | Yes | No |
| Transparency | Yes (via fill-opacity) | Yes (in PNG, WebP) |
| Gradient support | Yes | Yes |
| Photographic quality | No | Yes |
5. Where to use each format
| Task | What to choose |
|---|---|
| Logos, icons, diagrams, infographics | SVG |
| Photos, screenshots, textures, banner backgrounds | JPG / WebP |
| Transparent elements | SVG or PNG |
| Animations and interfaces | SVG (via CSS/JS) |
6. A visual example
| Scale 100% | Scale 500% |
|---|---|
| SVG: lines stay sharp | Quality does not change |
| JPG/PNG: "stair-stepping" appears | Blurry, pixels are visible |
Summary:
| Criterion | SVG | Raster (JPG, PNG, WebP) |
|---|---|---|
| Graphics type | Vector | Pixel-based |
| Quality when enlarged | Not lost | Lost |
| File size | Small (for simple shapes) | Can be large |
| Scalability | Perfect | Limited |
| Animation and interactivity | Supported | No |
| Best use case | Icons, logos, charts | Photos, background images |
In simple terms: SVG is like a blueprint that can be scaled infinitely. A raster image is a photograph, where every pixel is already fixed. SVG is ideal for graphics and interfaces, raster formats: for realistic images and photographs.
Short Answer
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