SVG vs PNG — Vector vs Raster Image Format
SVG (vector) and PNG (raster) represent fundamentally different approaches to storing image data. SVG stores mathematical shape descriptions that scale perfectly to any size, while PNG stores pixel values that become blurry when scaled up. The distinction matters enormously for icons, logos, and UI graphics — elements that must look sharp on both small screens and large retina displays.
Comparison Table
| Aspect | SVG | PNG |
|---|---|---|
| Image type | Vector — mathematical paths and shapes | Raster — fixed pixel grid |
| Scaling | Resolution-independent; perfect at any size | Blurry when scaled above original resolution |
| File size | Tiny for simple graphics; grows with complexity | Grows with pixel dimensions; good for complex images |
| Transparency | Full transparency and masking | Full alpha channel transparency |
| CSS/JS manipulation | Fully styleable and animatable with CSS and JavaScript when inline | Cannot be styled; only src attribute changes |
| Photography | Not suitable for photographs | Can store any image including photos |
| Accessibility | Text content searchable; can include <title> and <desc> | Requires alt text on <img>; text inside is not real text |
| Email clients | Limited support in email | Universal email client support |
When to Use SVG
Use SVG for icons, logos, illustrations, charts, maps, and any graphic element that must scale across multiple screen sizes and resolutions. Retina displays have 2x or 3x pixel density — SVG looks crisp on all of them with a single file. CSS-styleable SVG icons that change color based on theme are far more maintainable than PNG sprite sheets. SVG is also the right format for any graphic that JavaScript needs to animate or interact with.
When to Use PNG
Use PNG for screenshots, UI previews showing photographs, complex illustrations that would be impractical as vectors, and any image where the content is photographic in nature. PNG is also the fallback for environments where SVG may not display correctly — email newsletters, certain PDF viewers, and some CMS rich text editors work better with PNG.
Convert Between SVG and PNG
Render SVG files to PNG at a specified width and height using the Canvas API.
Render an SVG file onto a canvas and export it as a JPEG image with adjustable quality.
Convert any image into 16×16, 32×32, and 48×48 favicon PNG files with live previews.
Resize a PNG to 32×32 and export it as a favicon-compatible PNG for use as a browser icon.
FAQ
- Can I use SVG for social sharing images (OG images)?
- No. Open Graph and Twitter Card images must be JPEG or PNG. Social platforms and link preview crawlers do not render SVG. Generate OG images as PNG (commonly done server-side with libraries like Satori or Sharp).
- When is SVG larger than PNG?
- SVG becomes large when it contains many complex paths, embedded raster images, or verbose metadata from design tool exports. A detailed illustration with thousands of paths can be larger than a PNG at typical display size. Always run SVG through an optimizer like SVGO before serving.
- Can I animate PNG?
- APNG (Animated PNG) is a PNG extension for animation. It is supported in most modern browsers but not as widely as GIF. For web animations, animated SVG (CSS animations or SMIL) or animated WebP are generally better choices than APNG.