FFreeToolsVerse
Home/Tools/Developer Tools/REM to PX Converter

REM to PX Converter

Developer Tools

Convert rem to px and px to rem for responsive typography.

⚡ Instant🔒 Private, in your browser🆓 Free, no sign-up👥 For developers
Your data never leaves your browser. We do not store inputs.

What REM to PX Converter does

Rem To Px Converter converts between rem units and pixels using a root font-size you set (16px by default, matching most browsers), so you can translate CSS values in either direction without doing the math by hand. Enter a rem or px value and see the equivalent instantly — useful when a design spec gives you pixels but your stylesheet is built in rem.

FV
Reviewed by the FreeToolsVerse team · Last updated · How we check our tools

How to use REM to PX Converter

  1. Set the root font-size if it's different from the default 16px
  2. Enter a value in the rem field, or a value in the px field
  3. View the converted value update instantly in the other field
  4. Copy the result into your CSS

Who should use it

Made for developers. Typical uses:

  • Converting a Figma or Sketch spec given in pixels into rem for a responsive stylesheet
  • Checking what a rem-based font-size actually renders as in pixels on a default browser
  • Adjusting a project's rem values after changing the root font-size

Frequently asked questions

What's the default root font-size used?
16px, which matches the default browser font-size unless your CSS overrides it on the html element.
Why would my project use a custom root font-size?
Some frameworks or CSS resets set html { font-size: 62.5%; } to make rem math easier — set that value here to get accurate conversions for your actual project.
Is it free to use?
Yes, completely free.
Is my data sent anywhere?
No, the conversion is simple arithmetic that runs entirely in your browser.
What's the difference between rem and em?
rem is always relative to the root html font-size, while em is relative to the parent element's font-size — this tool converts rem specifically.

Learning resources

Explore more in Developer Tools, read the guides and articles, or see how we test our tools.

Share This Tool

TwitterFacebookLinkedIn

Related tools

PX to EM Converter

Convert pixel values to EM units for responsive web design.

Best for converting a design spec's pixel measurements into em units for a responsive CSS stylesheet

VW to PX Converter

Convert viewport width units (vw) to pixel values for responsive design.

Best for checking how a hero heading sized in vw will look on a common desktop resolution

CSS Unit Converter

Convert between CSS units like px, em, rem, vw, vh, and percentages.

Best for converting a fixed px value from a Figma or Sketch mockup into rem for scalable, accessible typography

CSS Formatter

Format and beautify messy CSS code with proper indentation.

Best for beautifying minified CSS for editing

More Developer Tools tools

Base32 EncoderBase64 Encoder DecoderColor Contrast CheckerCron ParserCSS FormatterCSS to Inline ConverterHash GeneratorHTML Formatter

Categories

Calculators43Converters43Developer Tools33Generators46Minifiers13SEO Tools20Text Tools23Validators15Network Tools6PDF Tools19Image Tools16Social Media Tools3Video Tools10AI Tools6