Why use REM instead of PX?

REM units are relative to the root font size, making them better for accessibility. When a user changes their browser font size settings, REM-based layouts will scale proportionally, whereas PX-based layouts stay fixed.

CSS Unit Converter

Free online CSS Unit Converter. Convert pixels to rem, em, vw, vh, and more instantly. Adjustable base font size for accurate web development and responsive design.

100% PrivateInstant ProcessingNo Upload Required

Free online css unit converter tool. Process your files securely in your browser - your data never leaves your device.

Configuration

Base Font Size (PX)

Commonly 16px

Viewport Width (PX)

Viewport Height (PX)

Rapid Unit Converter

Pixel Value (Input)

REMBased on 16px base size

1.000rem

EMBased on 16px parent size

1.000em

Point (PT)Standard print unit (1pt = 1/72 inch)

12.00pt

Percent (%)Relative to 16px base

100.0%

Viewport Width (VW)Based on 1920px viewport

0.833vw

Viewport Height (VH)Based on 1080px viewport

1.481vh

Key Features

PX to REM/EM conversion
Viewport unit support
Custom base font size
Real-time calculation

Common Use Cases

Responsive layout design
Standardizing font sizes
Mobile-first development

Frequently Asked Questions

More Web Tools

Discover other helpful tools in this category.

SQL Formatter

Format and beautify SQL queries

HTML Formatter

Beautify and format HTML code

CSS Formatter

Beautify and format CSS styles

URL Encoder/Decoder

Encode and decode URLs and components

URL Parser

Parse URLs into their base components

User Agent Parser

Parse User Agent strings for browser and device info

HTML Entity Converter

Encode and decode HTML entities

Color Converter

Convert between HEX, RGB, HSL, and CMYK formats