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Aug 08, 2026
Convert PX values to REM/EM units based on configurable root font size for responsive design.
| PX | REM | Preview |
|---|
REM units are relative to the root font size, making them ideal for responsive design. When users change their browser's default font size, REM-based designs scale proportionally.
REM is always relative to the root element's font size. EM is relative to the parent element's font size. This tool uses the root font size for EM conversion as well.
REM = PX ÷ Root Font Size. For example, 32px with a 16px base = 2rem.
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