SVG explained: why vector images scale to any size
Most image formats are made of pixels. SVG isn't — and that one difference is why logos and icons on the modern web are almost always SVG. Here's the idea, and when you'd still convert it to a PNG.
Pixels vs. instructions
A JPG or PNG is a grid of colored pixels. Blow it up past its native size and it goes blurry or blocky, because there's no more detail to show. An SVG (Scalable Vector Graphic) stores instructions instead — "draw a circle here, a line there, fill this shape blue." The browser redraws those instructions at whatever size you ask for, so an SVG is razor-sharp at any scale, from a favicon to a billboard.
Why the web loves it
- Infinite sharpness — one file looks perfect on every screen and every zoom level, including high-DPI "retina" displays.
- Tiny file size — for simple graphics like logos and icons, an SVG is often just a few kilobytes.
- Editable and styleable — SVG is text under the hood, so you can change colors with CSS or animate it.
What SVG is not for
SVG is for graphics — logos, icons, illustrations, charts. It's the wrong tool for photographs: a photo has millions of unique pixels that can't be described as shapes, so a "photo as SVG" would be huge and pointless. For photos, stick with JPG, PNG, or WebP.
When to convert SVG to PNG
Even though SVG is superior for the web, you sometimes need a plain pixel image:
- Uploading to a platform that rejects SVG — many social networks and marketplaces only accept PNG/JPG.
- Sending to software that can't read SVG — some older apps and templates.
- You need a fixed-size raster — for a thumbnail, an email, or an OG preview image.
Converting SVG → PNG "flattens" the instructions into pixels at a size you choose. Pick a resolution high enough for its use, since the PNG won't scale up cleanly the way the SVG did.