CSS Unit Converter
Convert between CSS units (px, rem, em, %, vh, vw) easily. Set custom root font size for accurate rem/em conversions. Essential for responsive web design.
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What is CSS Unit Converter?
CSS Unit Converter simplifies web design by translating values between PX, REM, EM, and Percentage based on your root font size.
Key Benefits
- Responsive design
- Base size control
- Bidirectional
- Clean interface
Common Use Cases
- •Frontend development
- •Responsive layouts
- •Accessibility
- •CSS refactoring
How to Convert CSS Units
- Enter value: Type the value you want to convert (e.g., 16).
- Set base size: Adjust the root font size if needed (default is 16px).
- Get results: Instantly view the converted values in all other units.
Key Features
- Convert between px, em, rem, %, vw, vh
- Configurable base font size
- Viewport dimension settings
- Real-time conversion
- Common conversion presets
- Copy converted values
Frequently Asked Questions
What is the standard base font size?
The standard base font size for most browsers is 16px. Our converter uses this default but allows you to customize it if your project uses a different base size.
Why use REM instead of PX?
REM units are relative to the root font size, making your design more accessible and responsive. Users who adjust their browser font size will see your site scale correctly with REMs.
When should I use EM vs REM?
Use REM for global sizing (font-size, padding) to maintain consistency. Use EM when you want sizing to be relative to the parent element's font size, useful for component-specific scaling.
How do percentages work in CSS type?
Percentage font sizes are relative to the parent element. 100% usually equals 16px (or the base size). They are precise but can compound in nested elements.