px ↔ rem Converter
CSS Unit Conversion: Convert between px and rem units essential for responsive web design. Supports improved accessibility and consistent scaling.
Standard: W3C CSS Values and Units Module Level 4 - rem unit (root element font size)
💡 Typically 16px
Conversion:
Advanced Settings
The px ↔ rem Converter converts between absolute px and relative rem units. Set a base font size and convert multiple values at once.
How to Use
- 1
Select mode: px → rem or rem → px.
- 2
Set base font size (default: 16px).
- 3
Enter values (comma/space/newline separated).
- 4
Convert automatically in Live mode or via button in Manual mode.
- 5
Copy results or download as a file.
Use Cases
Responsive Web Design
Use relative units to adapt to user settings.
Accessibility
rem scales with user font-size preferences across the UI.
CSS Refactoring
Convert px-based styles to rem for maintainability.
Design Systems
Use rem for consistent spacing and sizing scales.
px vs rem
px is absolute; rem is relative to the root element font size.
Conversion: rem = px / base, px = rem × base.
W3C CSS Values and Units: rem is predictable and accessibility-friendly.
Frequently Asked Questions (FAQ)
Q.Is my data safe?
A. Yes. All conversions run in your browser.
Q.How to set base font size?
A. Most browsers default to 16px. Use your project setting if different.
Q.When to use px vs rem?
A. Use rem for text/spacing; px for precise borders/layout when needed.
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