Drawing an icon that delights the eye is not enough. Making the icon scalable, responsive, and suitable for many devices is what’s important if you want someone to buy/use your icons. It requires a lot of thinking and experience, and that is what we’ve got. So tune in, and let us teach you how to create pixel-perfect icons.
Spoiler: video tutorial showing all the steps is also added at the end of the post.
We’ll be working in Adobe Illustrator. Start off by changing “Gridline every” parameter to 1px in Preferences -> Guides & Grid:

Also, open View menu and click Snap to Grid & Show Grid.
There are 6 key factors that define whether your icon is pixel perfect:
- Stroke width
- Inner elements
- Bezier curves
- Amount of details
- Perspective
- Scaling
Stroke Width
A linear icon can loose its sharpness if the stroke width is unrelated to with the pixel grid.

Video Call icon by Icons8
How to choose the stroke width? Always strive to use even numbers (2px, 4px, etc.). You can use odd numbers as well, just keep track of how they’re aligned with the grid.
Inner Elements
Inner elements of icons may be distorted if they aren’t aligned with the size of an icon. For example, if the circle has an even radius, say 20 px, the element inside should be even as well, e.g. 2 px.

High Importance icon by Icons8
Bezier Curves
You can fine tune vector paths in order to keep your edges clean.
Amount of Details

Icon by Webalys
Keep in mind that icon with a lot of small detail may look like a blurry spot when the icon is resized. So always design icons with a specific size in mind.
In order to solve this problem for our Office style icons, we draw every icon in 4 variations to fit any screen (16x16px and 30x30px are adapted for standard displays, 40x40px and 80x80px are for retina).
Perspective
Angled lines are more blurry. For small icons avoid perspective altogether, flat style is preferable.

Scaling
Beware of half pixels. If you make several sizes of the same icon, each size might require tweaking after scaling.
Watch the full video in which our designer Margarita guides you through the process step by step:
Also, welcome to review a checklist on icon design for graphic designers, check 6 temptations of icon designer and read what is favicon and why it’s important