Vector vs Raster: How to Pick the Right Image Type for the Job

A logo looks crisp on your website, then turns into a blurry, blocky mess the moment someone prints it on a banner. Or a print shop asks for "a vector file" and you are not sure whether the PNG you have counts.

Both problems come down to one distinction. Every digital image you work with is either raster or vector, and the two behave very differently once you resize, edit or print them.

Here is what each type actually is, where each one shines, and how to decide which to use for a given job.

What a raster image is

A raster image is a grid of tiny coloured squares called pixels. Each pixel stores one colour, and together they form the picture, much like tiles in a mosaic.

You will also hear raster images called bitmaps. The terms mean essentially the same thing, so "bitmap vs vector" is the same comparison under an older name.

Photos from your phone or camera are raster images. So are screenshots, scanned documents and most images you download from the web. Common raster formats include JPG, PNG, GIF, WebP, HEIC, TIFF and BMP.

The defining trait of a raster image is that its detail is fixed. A photo that is 1200 pixels wide contains exactly 1200 columns of colour information, no more.

What a vector image is

A vector image does not store pixels at all. It stores instructions: points, lines and curves described mathematically, along with the colours that fill or outline them.

Instead of saying "this pixel is red", a vector file says something closer to "draw a curve from here to here, then fill the shape with red". The curves are usually Bézier curves, the same kind you edit with the pen tool in design software.

Common vector formats include SVG, EPS and AI, the native Adobe Illustrator format. PDF is a special case, because a single PDF can hold vector shapes, raster images or both.

Fonts are vector too. That is why text stays sharp whether you set it at 9 points or blow it up to fill a poster.

The key difference between raster and vector

The real difference between raster and vector shows up when you change the size.

Enlarge a raster image and the software has to invent pixels that were never there. It smooths and guesses, and the result looks soft, blurry or blocky. Shrinking is safer, but you permanently throw detail away if you save over the original.

Enlarge a vector image and nothing is invented. The software simply recalculates the shapes at the new size, so the edges stay clean at 50 pixels wide or 5 metres wide.

It helps to know that every screen ultimately shows pixels. When you open an SVG, your browser converts the shapes into pixels on the fly, at whatever size is needed. Vector files just postpone that step until the last moment, which is exactly why they scale so well.

Pixel vs vector graphics: strengths of each

Neither type is better overall. Each is good at different things, and most real projects use both.

Raster images are strongest when you need:

• Photographic detail, with subtle gradients, textures and natural lighting
• Painted or textured artwork, such as digital painting and photo retouching
• Universal compatibility, since JPG and PNG open almost anywhere
• Pixel-level editing, like cloning, healing or masking parts of a photo

Vector images are strongest when you need:

• Logos and brand marks that must work on business cards and billboards alike
• Icons, illustrations and diagrams built from clean, flat shapes
• Small file sizes for simple graphics, especially on the web
• Easy edits, such as changing a colour or reshaping a curve without redrawing

There are trade-offs on both sides. A vector file cannot realistically represent a photograph of a forest; it would need millions of tiny shapes and still look flat.

On the other hand, a raster logo locks you into whatever resolution it was saved at. If the only copy is a 300-pixel PNG, you will run into trouble the first time someone needs it large.

Vector vs raster images on the web

On websites, the choice usually comes down to what the image shows.

Photos belong in raster formats. JPG and WebP handle photographs efficiently, while PNG is the usual pick when you need sharp edges or transparency in a raster image. If transparency is your sticking point, our guide on making a transparent background image covers which formats keep it and which quietly drop it.

Logos, icons and simple illustrations are often better as SVG. An SVG is plain text written in XML, so it is often very light, stays sharp on high-density screens and can even be styled or animated with CSS.

There is one caution with SVG. A very detailed vector drawing with thousands of anchor points can end up heavier than a well-compressed PNG, so "vector" does not automatically mean "smaller".

Raster vs vector for print, cutting and engraving

Print is where the wrong choice hurts most, because problems that are invisible on screen become obvious on paper.

For raster images, printers think in pixels per inch. A common rule of thumb for sharp prints viewed up close is around 300 pixels per inch at the final printed size. A 1200-pixel-wide image therefore prints cleanly at only about 4 inches wide.

That is why print shops ask for vector logos. With a vector file, they can print your mark on a flyer or a truck wrap from the same source without losing quality.

Cutting machines, vinyl plotters and laser cutters go a step further. They follow paths, so they need vector shapes to know where to cut. Laser engravers often support both modes: raster engraving burns an image line by line, while vector cutting follows outlines.

Software for working with each type

The tools you use tend to fall on one side of the line.

Raster editors include Adobe Photoshop, GIMP, Krita and Affinity Photo. They are built for painting, retouching and adjusting pixels.

Vector editors include Adobe Illustrator, Inkscape, Affinity Designer and Figma. They are built around paths, shapes and type.

Many modern apps blur the boundary a little. Photoshop can hold vector shape layers, and Illustrator can place photos, but each app is still most comfortable in its home territory.

Converting between raster and vector

Going from vector to raster is easy. Every vector editor can export a PNG or JPG at any size you choose, and you lose nothing from the original file.

Going from raster to vector is harder, because the software has to work out where the edges and shapes are. This process is called tracing, and it works best on images with clear outlines and a limited number of colours, such as logos, line art and signatures.

If you want to try it, our free PNG to SVG converter traces an image in your browser. For a deeper look at what happens during tracing and when the results are worth it, read how image tracing works.

Tracing a photograph rarely gives you what you want. The output either loses most of the detail or becomes a huge file full of tiny shapes, so photos are best left as raster images.

How to choose: a quick decision guide

When you are unsure which type you need, a few questions usually settle it.

Is it a photo or something with realistic texture? Use raster, saved as JPG, WebP or PNG depending on whether you need transparency.

Is it a logo, icon or simple illustration that might be resized later? Keep a vector master file, usually SVG or AI, and export raster copies when a platform demands them.

Will it be cut, plotted or engraved as outlines? Use vector, because the machine needs paths to follow.

Are you sending it to a printer? Send vector files for logos and type, and high-resolution raster files for photos, checked at the final print size.

Keep the master file

The most useful habit is simple. Keep the original vector file for anything you draw, and the full-resolution original for anything you photograph.

You can always make a smaller or rasterised copy later. What you cannot do is put back detail that was never saved, so start from the best source you have and export down from there.

Cover photo: David Revoy, CC BY 4.0, via Wikimedia Commons.