PX to EM Converter

Convert pixels to EM units instantly with our free px to em calculator for responsive design and accessible websites.

Default browser font size is usually 16px

px
em

Conversion Formula:

16px ÷ 16px = 1em

How to Use Our PX to EM Converter

Converting px to em is simple with our calculator. Learn how to convert pixels to EM units for responsive web design in three easy steps.

1

Enter Pixel Value

Type the pixel value you want to convert in the PX input field. The converter accepts whole numbers and decimals for precise measurements.

2

Set Base Font Size

Adjust the parent element's font size if needed (default is 16px, the browser standard). This base value determines your EM calculation.

3

Get EM Result

The converter instantly calculates the EM value. Copy the result and use it in your CSS for responsive, accessible web design.

PX to EM: Understanding the Difference

Before using our px to em converter, learn the key differences between pixels and EM units for responsive design and web accessibility.

What are Pixels (PX)?

Fixed Size Unit

Pixels are absolute units that stay the same size regardless of parent elements or user settings. 16px is always 16px.

Accessibility Limitation

Pixel-based font sizes don't respect user browser preferences, which can affect accessibility for visually impaired users.

Best Use Cases

Ideal for borders, shadows, and layout elements where precise control is needed and user scaling isn't required.

What are EM Units?

Relative to Parent

EM values are calculated relative to the parent element's font size. If the parent is 16px, then 1em equals 16px and 2em equals 32px.

Responsive Scaling

EM units automatically scale when parent font sizes change, making them perfect for responsive design and flexible layouts.

Accessibility Benefits

EM units respect user browser settings, allowing visually impaired users to increase text size for better readability.

PX to EM Conversion Formula

EM = Pixels ÷ Base Font Size

Default base font size is 16px (browser standard)

Example: 24px ÷ 16px = 1.5em

Example: 32px ÷ 16px = 2em

Example: 12px ÷ 16px = 0.75em

When to Use PX to EM Conversion

Knowing when to convert px to em is essential for CSS best practices. Use our px to em converter for these common scenarios.

Use EM Units For:

  • Font sizes that should scale with parent elements
  • Padding and margins within components
  • Responsive typography and spacing
  • Accessible designs that respect user preferences
  • Modular components that scale proportionally

Use Pixels For:

  • Borders and border widths
  • Box shadows and outline styles
  • Fixed-size icons and images
  • Precise layout measurements
  • Elements that should never scale

PX to EM Converter FAQ

Common questions about our px to em calculator and converting pixels to EM units in CSS.

What is the difference between EM and REM units?

EM units are relative to the parent element's font size, while REM units are relative to the root (html) element's font size. EM values can compound in nested elements—for example, a 1.5em element inside another 1.5em element becomes 2.25em. REM units stay consistent throughout the page since they always reference the root font size. Use EM when you want elements to scale with their parent, and REM for consistent sizing across your site.

Why should I use a PX to EM converter?

Using a px to em converter helps create accessible and responsive websites. When you convert px to em, your designs respect user browser settings—if users increase their default font size for better readability, EM-based elements scale accordingly. A px to em calculator ensures accurate conversions, making your CSS more flexible and user-friendly.

How do I calculate PX to EM conversion manually?

The px to em conversion formula is simple: divide the pixel value by the parent element's font size (EM = Pixels ÷ Parent Font Size). For example, to convert 24px to em with a 16px parent font size: 24 ÷ 16 = 1.5em. Our px to em converter does this calculation instantly, but understanding the formula helps you work with EM units effectively.

Should I use EM units for media query breakpoints?

While you can use EM in media queries, it's generally better to use REM or pixels for breakpoints. Media queries with EM units calculate based on the browser's default font size (typically 16px), which can be confusing. REM units in media queries provide more predictable behavior and respect user font size preferences for better accessibility.

When should I use PX instead of EM?

Use pixels for elements that should stay fixed regardless of font size changes, such as borders (1px border), box shadows, precise spacing in layouts, and fixed-size images or icons. Pixels give you exact control and prevent unwanted scaling. For typography, padding, margins, and responsive elements, EM or REM units are usually better choices.

Related Tools

PX to REM

Convert pixels to REM units

16px = 1rem (default)

PX to PC

Convert pixels to picas

1pc = 16px (96dpi)

PX to PT

Convert pixels to points

1pt = 1.33px (96dpi)

PX to MM

Convert pixels to millimeters

1mm = 3.78px (96dpi)

Try Our PX to EM Converter Now

Convert px to em instantly with our free calculator. Start building more accessible and responsive websites today.

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