The core difference: maths versus pixels
An SVG is a vector. The file does not store a grid of coloured dots. It stores instructions: draw a circle here, fill it blue, run a line from this point to that one. The browser reads those instructions and paints the shape fresh at whatever size you ask for. Scale it to a postage stamp or a billboard and the edges stay sharp, because they are recalculated every time.
A PNG is a raster. It stores an actual grid of pixels, each with a fixed colour. That grid has a set resolution. Blow it up past its native size and the browser has to guess what goes between the pixels, so edges turn soft and blocky. PNG also supports transparency, which is why it beats JPEG for graphics that need to sit over a coloured background.
So the split is simple. SVG is drawn from maths and scales without limit. PNG is a fixed photograph of pixels and looks best at the size it was made.
Where SVG wins
Anything built from clean shapes belongs in SVG. Logos, icons, UI elements, line art, charts, flat illustration. These are made of paths and fills, exactly what SVG describes best, so the file stays tiny. A simple icon can be a few hundred bytes.
Two other advantages matter. SVG stays editable forever, because the shapes are still shapes and not baked into pixels. You can reopen it, change a colour, nudge a point. And because it scales infinitely, one SVG logo serves your favicon, your website header and a printed banner without a second export.
Where PNG wins
Photographs and anything with fine detail, gradients or texture should be PNG. A photo has thousands of subtly different colours across the frame. Describing that as vector shapes would be absurd, and the file would be enormous. Pixels are the honest way to store it.
PNG is also the safe choice when you need a raster with transparency, such as a product shot cut out from its background, or a screenshot with rounded corners. It is widely supported and no software will ever refuse it.
A quick decision guide
Use SVG when the image is a logo, icon, symbol, chart or flat illustration; when it needs to scale to different sizes; or when you want to keep editing it later.
Use PNG when the image is a photo or has photographic detail; when you need a fixed-size raster with transparency; or when you are handing a file to a system that only accepts pixels.
One practical trick: many teams design a graphic as SVG, then export a PNG at the exact size a given platform wants. You get the clean editable master and the flat delivery file, from the same source.
Editing SVG, exporting both
If you work with vector graphics, it helps to use a tool where the document is genuinely SVG rather than a copy exported at the end. Rayzia is a free, browser-based editor built exactly that way: the file you edit is the SVG. When you are done you can export SVG for the scalable master, or PNG when a platform wants pixels. It runs in any browser with nothing to install, so you can open the editor and try it on a real file in a minute.
Common questions
Is SVG better than PNG?
Neither is better overall; they solve different problems. SVG is better for logos, icons and flat illustration because it scales to any size and stays editable. PNG is better for photos and images with fine detail, because those are made of pixels rather than shapes. Choose by what the image actually is.
Can I convert a PNG to SVG?
Not cleanly in most cases. A PNG is pixels, and turning pixels back into vector shapes requires tracing, which guesses at the outlines and rarely matches the original. It works reasonably for simple, high-contrast graphics like a plain logo, but not for photos. If you have the choice, keep the original as SVG from the start.
Why is my PNG logo blurry when I scale it up?
Because a PNG has a fixed number of pixels. When you enlarge it beyond its native size, the software has to invent pixels that were never there, which softens the edges. A logo saved as SVG avoids this entirely, since it is redrawn from maths at every size.
Does SVG support transparency like PNG?
Yes. SVG handles transparency, partial opacity and blending, and often does it more flexibly than PNG. The difference is not transparency but how the image is stored: SVG as shapes, PNG as pixels.