Vector Images: What They Are & How to Make One

A vector image is a digital graphic defined by mathematical formulas—points, lines, curves, and shapes—rather than a fixed grid of pixels. You create one in vector-editing software like Adobe Illustrator or the free Inkscape, and you view it with any modern browser, image viewer, or design program that supports SVG, EPS, PDF, or AI files. Unlike raster images (JPEG, PNG), vectors stay sharp at any size, making them essential for logos, illustrations, and anything you need to scale without losing quality.

Formula

The calculator above converts a raster image’s pixel dimensions to physical print size at a given resolution, and also gives the total megapixel count. The formulas are:

• Print width (inches) = width in pixels ÷ PPI
• Print height (inches) = height in pixels ÷ PPI
• Megapixels = (width × height) ÷ 1,000,000

Where PPI (pixels per inch) is the resolution of the image file—commonly 72 for screen, 300 for print. The result tells you how large the raster image can be printed before it starts looking pixelated.

Worked Example

Using the defaults: width = 800 px, height = 600 px, PPI = 300.

1. Print width = 800 ÷ 300 = 2.67 inches
2. Print height = 600 ÷ 300 = 2.00 inches
3. Megapixels = (800 × 600) ÷ 1,000,000 = 0.48 MP

So an 800×600 image at 300 PPI prints at 2.67 × 2.00 inches—roughly a 2.5×2 inch photo. To print larger, you need more pixels or a lower PPI (which reduces sharpness).

What Is a Vector Image?

A vector image stores graphics as paths—each path has a start point, end point, and control points that define curves. The file records the coordinates and the mathematical relationship between them. When you zoom in, the software recalculates the curves for the new scale, so edges stay smooth. Common vector formats include:

• SVG (Scalable Vector Graphics) – the web standard, text-based, supported by all browsers.
• EPS (Encapsulated PostScript) – older print-industry standard.
• PDF – can embed vector graphics; often used for sharing.
• AI – Adobe Illustrator’s native format.

In contrast, a raster image (like a JPEG) is a grid of colored squares (pixels). Zoom in enough, and you see the squares; the image becomes blurry or blocky. Vectors have no such limit.

How Vector Images Work

Every vector graphic is built from basic geometric objects: points, lines, curves (Bezier curves), and filled shapes. For example, a circle in SVG might look like:

<circle cx="50" cy="50" r="40" fill="red" />

That one line tells the computer to draw a red circle centered at (50,50) with radius 40. Because it’s a formula, you can scale it to 4000 pixels wide and it still renders perfectly.

When you edit a vector, you move control handles to change the curve’s shape. The file stores the handle positions, not a bitmap of the curve. This is why vector files are often much smaller than high-resolution rasters for simple graphics—but complex illustrations with thousands of paths can become large.

How to Make a Vector Image

You create vectors using dedicated software. The process is the same whether you draw from scratch or trace an existing image.

1. Choose software – Adobe Illustrator (paid), Inkscape (free), Affinity Designer (paid), or CorelDRAW (paid).
2. Create shapes – Use the pen tool to draw paths, or combine basic shapes (rectangles, circles, polygons).
3. Edit points – Adjust anchor points and handles to refine curves.
4. Apply fills and strokes – Set colors, gradients, and line widths.
5. Save in a vector format – SVG for web, PDF for sharing, EPS for print, or AI for further editing.

If you have a raster logo or drawing you want as a vector, you can trace it. Most vector apps have an auto-trace feature that converts pixel edges into paths. The result often needs manual cleanup.

How to View a Vector Image

Viewing a vector is easy—most devices handle them natively:

• SVG – Opens in any web browser (Chrome, Firefox, Safari, Edge).
• PDF – Opens in Adobe Acrobat, browsers, and most image viewers.
• EPS – May need a dedicated viewer (like Ghostscript) or a design program; Windows Photos can’t open EPS by default.
• AI – Requires Illustrator or a compatible viewer; many free tools can’t open AI files.

For quick viewing, convert the file to SVG or PDF using free online converters. If you just need to look at it, a browser is the most universal viewer.

Vector vs. Raster: Which Should You Use?

Choose vector when you need scalability, editability, or small file size for simple graphics. Choose raster when you have complex continuous-tone images like photographs.

Factor	Vector	Raster
Scaling	Infinite, no quality loss	Loses quality when enlarged
File size	Small for simple graphics	Large for high resolution
Editability	Easy to change shapes/colors	Hard to edit without artifacts
Best for	Logos, icons, illustrations, text	Photos, complex gradients, textures

A common misconception is that vector images are always better. That’s false—a photo of a sunset has millions of color variations that would take an enormous number of paths to replicate, making the file huge and still not perfect. Rasters are the right tool for continuous-tone images.

Common Problems and How to Avoid Them

• Pixelated output – If you export a vector to a raster format (like JPEG) at too low a resolution, it will look pixelated. Export at the final size you need.
• Missing fonts – If a vector file uses a font not installed on the viewer’s system, text may render differently. Convert text to curves (outlines) before sharing.
• Compatibility issues – Some programs can’t open AI or EPS files. Stick to SVG or PDF for universal compatibility.
• File bloat – Too many paths or embedded rasters can make a vector file large. Simplify paths and avoid embedding unnecessary images.

Frequently Asked Questions

Can I convert a JPEG to a vector image?

Yes, but not automatically with perfect results. You use tracing software (like Illustrator’s Image Trace or Inkscape’s Trace Bitmap) that converts pixel edges to paths. For simple logos with flat colors, tracing works well. For photos, the result is usually messy and not worth the effort.

What is the best free vector editor?

Inkscape is the most popular free, open-source vector editor. It supports SVG, EPS, PDF, and many other formats. It has a steeper learning curve than some paid tools, but it’s capable of professional work.

Why does my vector image look blurry when I open it in Windows Photos?

Windows Photos is a raster viewer—it doesn’t render vector formats natively. When you open an SVG or EPS, it may convert it to a bitmap at a fixed size, causing blurriness. Use a browser or a vector-capable viewer instead.

What does SVG stand for?

SVG stands for Scalable Vector Graphics. It’s an open standard maintained by the W3C, designed for displaying vector graphics on the web. It’s text-based, so it can be searched, indexed, and edited with code.

Are vector images always smaller than raster images?

No. A simple vector logo is tiny compared to a high-res PNG, but a vector illustration with thousands of paths can be larger than a modest JPEG. File size depends on complexity, not just the format.

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in w | Width | px | 800 | 1 | 10000
in h | Height | px | 600 | 1 | 10000
in ppi | PPI (pixels per inch) | - | 300 | 72 | 1200
out dpi_w | Print width at PPI | in | w / ppi | 2
out dpi_h | Print height at PPI | in | h / ppi | 2
out mp | Total megapixels | MP | (w * h) / 1000000 | 2