PX to REM Converter

Convert between pixels and REM units for responsive CSS

Base Font Size:
px
(Default: 16px)

PX → REM

px =
1 rem

REM → PX

rem =
16 px

Common Conversions (16px base)

Pixels REM Use Case
8px0.5remSmall spacing
12px0.75remSmall text
14px0.875remBody text
16px1remBase text
20px1.25remLarge text
24px1.5remHeadings
32px2remLarge headings
48px3remHero text

What is REM in CSS?

REM stands for "Root EM". It's a relative CSS unit that's based on the font size of the root element (html). By default, 1rem equals 16px in most browsers. Using REM units makes your designs responsive and accessible, as they scale proportionally when users change their browser's default font size.

Unlike pixels (px) which are absolute, REM units respect user preferences and are essential for creating accessible, scalable websites.

Frequently Asked Questions

Why use REM instead of PX?

REM units respect user browser settings. If a user increases their default font size, REM-based designs scale accordingly, improving accessibility for people with visual impairments.

What's the difference between REM and EM?

REM is always relative to the root (html) font size. EM is relative to the parent element's font size, which can lead to compounding issues in nested elements.

Can I change the base font size?

Yes! Use our custom base size slider above to convert for any base font size. The default is 16px, but many designs use 10px for easier math (1rem = 10px).