PX to REM Converter & CSS Unit Calculator
Convert pixel values to accessible, responsive REM units based on your project's root HTML font size. Generates copyable CSS rules and a full typography scale.
How to Use PX to REM Converter & CSS Unit Calculator
Set Base Font Size
Default is 16px (browser standard); adjust if using a custom HTML font size.
Enter Pixel Value
Type any pixel dimension (e.g. 24px) or use the interactive slider.
Copy REM Value
Copy the calculated REM value (e.g. 1.5rem) or complete CSS snippet.
About PX to REM Converter & CSS Unit Calculator
Computes REM = Pixels / BaseFontSize, producing relative units that scale when users adjust default browser text accessibility settings.
Supported Formats
Operational Limits
- •Assumes standard linear browser root font sizing.
Key Features
- Configurable root font size (default 16px)
- Bidirectional pixel-to-rem calculation
- Common font size reference scale table (12px to 72px)
- Instant CSS declaration copy (font-size, padding, margin)
- One-click copy to clipboard
Frequently Asked Questions
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