PNG vs SVG: A Practical Guide to Transparency, Losslessness, and Pixels
Compare PNG and SVG across zoom behavior, transparency, lossless compression, and decode cost to choose the right format for each scenario.
PNG and SVG are both popular image formats, but they work in very different ways. PNG stores pixels, while SVG stores shapes as code. Choosing the right one depends on the image type, how it will be used, and whether it needs to scale without losing quality.
How Each Format Works
PNG is a raster format. It stores a grid of pixels and supports transparency. It is reliable for screenshots, photos with text, and graphics where every pixel matters.
SVG is a vector format. It stores paths, shapes, and text as instructions. It can be scaled to any size without becoming blurry, and it can be edited with code.
Comparison
| Property | PNG | SVG |
|---|---|---|
| Structure | Pixels | Vector shapes |
| Scaling | Can become blurry | Always sharp |
| Transparency | Yes | Yes |
| Text | Rendered as pixels | Editable text |
| File size | Depends on resolution | Depends on complexity |
| Animation | Not native | Possible |
When to Use PNG
Use PNG when:
- The image is a screenshot or scanned document.
- It contains complex textures or photographs.
- You need a raster file for compatibility.
- The image includes pixel-level details that should not change.
When to Use SVG
Use SVG when:
- The image is a logo, icon, or simple illustration.
- It needs to scale across different screen sizes.
- You want to control colors with CSS.
- You need a small file size for simple graphics.
Converting Between PNG and SVG
Converting SVG to PNG is straightforward: render the vector image at the desired resolution and export it as a raster file. Converting PNG to SVG is harder because it requires tracing the pixels into vector paths. Simple logos and shapes can be traced successfully; photographs cannot be converted effectively.
PictKit's SVG converter can convert SVG to PNG or WebP at different sizes, which is useful when you need a raster version for email, documents, or platforms that do not support SVG.
Decision Checklist
- Is the image a photo or complex texture? Use PNG or a raster format.
- Does it need to stay sharp at any size? Use SVG.
- Does it need transparency? Both formats support it.
- Will you edit it as code or style it with CSS? Use SVG.
- Does the target platform require a raster file? Use PNG.
There is no format that is best for everything. Matching the format to the image type and use case prevents avoidable file size and quality problems.
FAQ
Is SVG always better than PNG? No. SVG is better for simple vector graphics, but PNG is better for photos, screenshots, and complex textures.
Can SVG be used in HTML? Yes. SVG can be embedded directly in HTML and styled with CSS.
Why is my PNG so large? PNG stores pixels without lossy compression, so high-resolution images can be large. Convert to WebP or use JPEG for photos when file size matters.
Can I use SVG for a favicon? Yes. Modern browsers support SVG favicons, and you can provide PNG or ICO fallbacks for older browsers.