Instant PX to
REM Converter

Instantly Convert Pixels to the
CSS Unit Rem, and Vice Versa.

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How to Use Instant PX to REM Converter

This cool calculator instantly converts pixels to the CSS unit REM.

By default, the calculator assumes a font size of 16 pixels, which is pretty common in web development. But you can tweak that.

How do I use it?

Pretty Simple: The calculations happen as you type, and you can simply click the copy button to copy the result to your clipboard.

​Like this:

How about Px to Pt?

You bet …

Convert PX to Other Units

You can also convert: Px-Pt, Px-Cm, Px-Em, Px-Mm

Yep, you can turn pixels (px) into points (pt), centimeters (cm), ems (em), or millimeters (mm), super fast.

Wow! Thanks👍

The Basics: Pixels and REM

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A Pixel: often denoted as ‘px’, is a fixed-size unit of measurement in digital screens. This unit corresponds to the smallest point a screen can render. This measurement remains consistent regardless of any other factor, making it an absolute unit of measurement.

On the other hand, REM, which stands for ‘Root EM’, is a relative CSS unit that’s relative to the font-size of the HTML root tag. This measurement provides a certain flexibility in terms of design, especially for responsive layouts.

For instance, using the default font-size (which is typically 16 pixels), 1 REM would be equivalent to 16 pixels. On the contrary, 1 pixel would equate to 0.0625 REM. This conversion is bidirectional, meaning you can convert pixels to REM and vice versa by adjusting the base root font size accordingly.​

EM Vs REM Units

Just like REM, EM is a relative unit of measurement in CSS. However, while REM is always relative to the root font size, EM is relative to its closest parent font size, which can vary among elements.

This difference is important to note because it could have a huge impact on the look and feel of your website. REM maintains its consistency throughout a document, making it a safer and more predictable choice for many developers. Meanwhile, EM can provide more flexibility but may also introduce complexity due to its variability among parent elements.

It’s also worth noting that REM is a newer unit compared to EM, and while most modern browsers support it, some older ones might not. Always ensure you test your designs across multiple browsers to ensure the best compatibility.

What’s Wrong With Pixels

While it wouldn’t be accurate to say that using pixels is inherently “bad” …

There are certain aspects of pixels that might make them less suitable for certain use cases, especially in the context of modern web design.

Lack of Scalability and Responsiveness

Pixels are fixed units of measurement that don’t adjust or scale based on user settings or screen sizes.

In an era where web content is consumed on a variety of devices with different screen sizes and resolutions, from small mobile phones to large desktop monitors, this can be problematic.

For instance, a font size of 16px will always be 16 pixels tall, regardless of whether it’s being viewed on a mobile device or a 4K monitor. This can lead to legibility issues on high-resolution displays or for users with visual impairments who may need larger text.

No Relative Sizing

When you specify measurements in pixels, those sizes are absolute, and they don’t adjust relative to other elements. This makes building modular, scalable designs more challenging.

In contrast, relative units like EM and REM adjust based on other factors (either the font size of the parent element or the root element, respectively), which can make your design more adaptive and flexible. For example, increasing the root font size will proportionally increase all sizes defined in REMs, something that isn’t possible with pixels.

Accessibility

Pixels are absolute units and don’t respect the default font size of the browser. Many users will adjust their browser’s default font size for accessibility reasons, and using pixels for font sizes can lead to text that is too small to read comfortably.

In contrast, using relative units such as REMs will respect the user’s browser settings and scale appropriately, leading to a more accessible design.

PX to REM Conversions

Converting pixels to REM and vice versa is pretty straightforward.

Once you understand the fundamental relationship. To convert pixels to REM, divide the pixel value by the base font size. For the opposite conversion (REM to pixels), multiply the REM value by the base font-size.

For example, if you’re working with a base font-size of 16 pixels (which is standard), converting 32 pixels to REM would look like this:

32px / 16 = 2rem (And converting 2rem to pixels would be: 2rem * 16 = 32px)

Easy, isn’t it?