Pixel to Rem Converter

Convert px ↔ rem for responsive CSS

ConvertersFreeNo Signup
4.4(265 reviews)
All Tools

Loading tool...

About Pixel to Rem Converter

A pixel-to-rem converter for responsive web development. Convert individual values or entire lists between px and rem units with a customizable base font size (default 16px). Shows bidirectional conversion, generates CSS-ready output, and includes a common sizes reference table. Essential for web developers implementing responsive typography, spacing, and layout systems.

Pixel to Rem Converter Features

  • px ↔ rem
  • Custom base size
  • Batch conversion
  • CSS output
  • Common sizes table
In CSS, rem (root em) units are relative to the root element's font size (typically 16px). Using rem instead of px creates more accessible and responsive designs because users can scale text via browser settings. Converting between px and rem is a frequent task in front-end development.

How to Use

Convert values:

  • Single: Enter a px or rem value
  • Base size: Set root font size (default: 16px)
  • Batch: Enter multiple values separated by commas

Conversion Formula

rem = px / base_font_size. With the default 16px base: 24px = 24/16 = 1.5rem. Conversely: 2rem = 2 × 16 = 32px.

Best Practices

  • Use rem for font sizes and spacing for accessibility
  • Use px for borders, shadows, and fine details
  • Set a base font size on html element (typically 62.5% = 10px for easy math)
  • Use em for component-relative sizing

Step-by-Step Instructions

  1. 1Enter a pixel or rem value.
  2. 2Adjust the base font size if needed.
  3. 3View the converted result.
  4. 4Copy the CSS-ready output.
  5. 5Check the common sizes reference.

Pixel to Rem Converter — Frequently Asked Questions

Why use rem instead of px?+

Rem units respect user browser settings for text scaling (accessibility). If a user sets their browser to 150% text size, rem-based layouts scale appropriately while px-based layouts don't.

What's the difference between em and rem?+

em is relative to the parent element's font size (can compound). rem is always relative to the root (html) element's font size (predictable). rem is generally preferred for consistency.

Why do some developers set font-size: 62.5% on html?+

62.5% of 16px = 10px base. This makes mental math easy: 1.6rem = 16px, 2.4rem = 24px. However, this can break third-party components that assume a 16px base.

More Converters Tools

Explore all 46 other converters tools available on Generatr

Angle ConverterASCII Value ConverterBase Converter CalculatorBase64 Encoder / DecoderBinary / ASCII / Hex ConverterBinary to Text ConverterBinary/Decimal/Hex ConverterBraille TranslatorCode Beautifier / FormatterComplex Number Polar ConverterCSV to JSON / XML ConverterCSV to JSON ConverterCurrency & Crypto ConverterCurrency ConverterDecimal to Fraction ConverterEpoch / Unix Timestamp ConverterFraction to Decimal ConverterFun Text TranslatorHex ↔ RGB Color ConverterHex Color ConverterHex to Decimal ConverterHex to RGB ConverterHTML / CSS / JS MinifierJSON / XML / SQL MinifierJSON to CSV ConverterJWT DecoderLength & Distance ConverterMarkdown to HTML ConverterMorse Code TranslatorNumber Base Converter
View all 46 converters tools
Share this tool: