px / rem Converter
Convert between px and rem. Adjustable base font size.
▶About this tool
This tool converts px and rem in one click. Three features: 1) Instant conversion from px or rem input, 2) Adjustable base font size (default 16px), 3) Useful for responsive and accessible CSS design. Ideal for converting design px to rem.
Tool interface
px
rem
Usage
- Enter px or rem value in the input field
- Converted value is displayed instantly
- Base font size (default 16px) is adjustable
When to use
Converting design px to rem, accessible font sizing, responsive spacing.
Examples
16px = 1rem, 24px = 1.5rem (base 16px).
FAQ
What's the difference between px and rem?
px is absolute (1px = 1 pixel). rem is relative to root font-size. 1rem = 16px when root is 16px.
What is rem based on?
Root element (html) font-size. Default 16px so 1rem=16px. html{font-size:62.5%} makes 1rem=10px for easier math.
Why use rem for responsive?
Change root font-size to scale everything. Fewer media queries. Respects user browser settings for accessibility.
How many px is 1rem?
Depends on base. Default 16px → 1rem=16px. Check your html font-size.
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