EM to PX Converter

Converting EM units to pixel (px) values is a common task in web development. This converter helps you quickly transform EM values to their equivalent pixel values based on the parent element's font size.

What are EM Units?

EM is a relative unit of measurement in CSS that is relative to the font-size of the parent element. If the parent element has a font-size of 16px (the browser default), then 1em equals 16px. If the parent element's font-size is 20px, then 1em equals 20px.

What are Pixel Units?

Pixels (px) are absolute units that represent a single dot on a screen. They are fixed-size units that will always render at the same size regardless of other styling. Pixels are commonly used for precise layouts and when you need exact control over element dimensions.

Conversion Formula

To convert from EM to pixels:

pixels = em × parent_font_size

Where:

• em is the EM value you want to convert
• parent_font_size is the font size of the parent element (default: 16px)

EM vs REM Units

While both EM and REM are relative units, they have a key difference:

• EM is relative to the font-size of its direct parent element
• REM is relative to the font-size of the root element (html)

This means EM units can compound when nested elements inherit font sizes, while REM units always refer to the same base value regardless of nesting.

When to Use EM Units

EM units are particularly useful for:

• Creating scalable components that adapt to their parent context
• Building responsive designs that maintain proportions
• Setting margins and padding relative to font size
• Creating modular components that can be reused in different contexts

Browser Support

Both EM and pixel units have excellent browser support across all modern browsers, including mobile browsers. They are safe to use in production environments.