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px to rem
Convert CSS pixel values to rem and browse a reference table
About px to rem
px to rem lets you convert css pixel values to rem and browse a reference table.
Category: Converters.
Frequently asked questions
What is the difference between px and rem?
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px is an absolute unit — 16px is always 16px. rem (root em) is relative to the root font size (typically 16px). 1rem = 16px by default, 1.5rem = 24px. rem scales with user font preferences and browser zoom.
Why use rem instead of px?
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rem respects the user's browser font size setting. Users who set their browser to a larger font size for accessibility will benefit from rem-based layouts. px values stay fixed regardless.
What if my root font size is not 16px?
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Enter your custom root font size in the tool. Many design systems set html { font-size: 62.5% } (10px) so that 1rem = 10px for easier mental math.