REM to PX Converter

Multiply the REM value by the root font size, which is 16px in almost all browsers by default. For example, 1rem = 16px, 0.5rem = 8px, and 1.5rem = 24px. This tool does the calculation instantly, including for fractional values like 0.125rem or 0.375rem.

REM (Root EM) is a CSS unit relative to the root element's font size. If the root font size is 16px, 1rem equals 16px. REM scales automatically when the root font size changes, which makes it ideal for responsive typography and flexible layouts.

Utility frameworks build their spacing and sizing scales on small REM increments (often 0.125rem, equal to 2px at the default base size) so that every utility class lines up on a consistent grid. That's why you'll see values like 0.375rem, 0.625rem, or 1.125rem in their design tokens.

PX (Pixel) is an absolute unit in CSS representing a single dot on the screen. Pixels are fixed in size and do not scale with the browser's font settings, which makes them useful for elements needing precise control, like borders or icons, but less flexible for responsive layouts.

REM units offer better accessibility and scalability compared to pixels. They adjust based on the root font size, making your website more responsive across devices and user settings. Pixels remain fixed, which can limit flexibility in responsive designs.

Yes. REM values are always relative to the root font size. If your CSS sets a different root size (e.g., 20px), then 1rem equals 20px, and every converted value shifts accordingly. Use the base font size field to convert with a different root size.

Yes. The input accepts any decimal value, so 0.125rem, 0.375rem, 0.9375rem, 2.4rem, and similar values all convert instantly and precisely.

The swap button switches focus between the REM and PX input fields, so you can quickly enter a value in one unit and see the converted result in the other without manually clicking into the other field.

Yes. Conversions are precise to 4 decimal places, based on the standard formulas: px = rem × 16 and rem = px / 16.

Absolutely. This page includes a common-values table for typical fractional REM sizes, plus full REM-to-PX and PX-to-REM reference tables, so you can look up conversions without typing anything. Every value links to its own page with more detail.