Two different ways of storing an image
A raster image is a fixed grid of colored pixels — a photo, a scan, and every image an AI generator produces. It has a maximum resolution set the moment it's created, and enlarging it means stretching that same fixed number of pixels across more space.
A vector image is built from mathematical paths and curves instead of pixels — shapes defined by equations, not a grid. It can be scaled to any size, from a favicon to a billboard, and the edges stay perfectly sharp at every size, because the math is recalculated, not stretched.
When to use raster vs. vector, in one line
If the file will ever need to print blurry text or soft, jagged edges at a bigger size than it was made for, it needs to be vector. If it will only ever exist at roughly the size it is now, raster is fine. The rest of this guide explains why.
When raster is genuinely fine
Most AI-generated artwork is meant to stay raster, and that's correct. A photo-style illustration, a textured background, a piece of wall art printed at the size it was generated for — these have detail, gradients and texture that vector paths aren't built to represent anyway. Converting a photorealistic image to vector doesn't make it better, it just makes it a (usually worse) cartoon version of itself.
When you actually need vector instead
Vector matters specifically when a design needs to work at more than one size, or needs perfectly crisp, simple edges: logos, wordmarks, icons, line-art illustrations, and anything going onto signage, embroidery, or laser engraving. These uses share one requirement raster can't meet — scaling up without softening — which is exactly what vector paths solve.
A good rule of thumb: if you can picture the same design needing to work both as a tiny favicon and a large storefront sign, it needs to be vector. If it only ever needs to exist at roughly the size it was created, raster is usually the right call.
How to tell which one you have
- File format is a strong hint, not a guarantee. .jpg, .png and .webp are always raster. .svg, .eps and .ai are usually vector, but a raster image can be embedded inside a vector-format file without actually becoming vector artwork.
- Zoom in past 400%. A raster image starts showing soft or blocky pixels. A true vector shape stays perfectly sharp no matter how far you zoom.
- Try selecting individual shapes in design software. Vector paths select as editable shapes and curves. A raster image selects as one flat block of pixels, with nothing underneath to edit.
Our free Vector vs Raster Checker identifies which one your file actually is, instantly, with no upload to a server.
Converting one to the other
Raster to vector (for a logo or icon) means a redraw — either by hand, which holds up at any size, or with auto-trace software, which technically produces paths but usually also traces the blurry edges and inconsistencies already in the image, and rarely holds up well at logo scale. Vector to raster is the easy direction: any vector file can be exported as a raster image at whatever resolution you need, since you're going from infinitely scalable math down to a fixed pixel grid.