REM to PX Converter
Translate REM units back into exact pixel values for your CSS, using your project's root font size. Free and instant.
About REM to PX Converter
A rem to pixel converter answers a question developers hit constantly: what pixel value is that rem actually producing? Design mockups are almost always delivered in pixels, yet production stylesheets frequently use rem units. When you need to compare your rem-based spacing against a fixed design spec, or explain to a designer why something is 24px and not 30px, this tool gives you the exact number in a moment.
Conversion works by multiplying the rem value by the root font size. With the standard 16px root, 1rem equals 16px and 2.5rem equals 40px. The root size is adjustable, which matters because many projects override it on the html element for accessible scaling or simpler math. Negative rem values used for negative margins convert correctly too, and fractional rem values produce exact fractional pixels rather than being truncated.
Frontend developers use it to sanity-check computed values while debugging spacing or to translate mockup dimensions into rem notation. Designers converting a design system's spacing scale, QA testers verifying implementations, and anyone learning how relative CSS units behave will get immediate, accurate answers. It is especially useful during audits, where you need to confirm that every token in your CSS resolves to the value intended in the design file.
How to Use
- Type the REM value you need to convert in the REM field.
- Adjust the root font size if your project doesn't use the 16px default.
- Copy the resulting pixel value to use in your stylesheet.
Example
1.5rem at a 16px root font size 24px
REM values multiply against the root font size, so 1.5 × 16 = 24px. This is handy when you must match a fixed design mockup that uses pixels.
FAQ
How do I know what root font size my project uses?
Check your stylesheet for a font-size rule on the html selector. If none exists, the browser default of 16px applies.
Why convert REM to pixels at all?
Design mockups are usually produced in pixels, while modern codebases use REM. Converting lets you translate between the two without mental math.
Does this work for negative REM values?
Yes, negative values such as -0.5rem convert correctly, which is useful for margins and offsets with negative spacing.
Is 1rem always 16px?
Only when the root font size is 16px. If your page sets a different size on the html element, 1rem equals that value. Always match the root size here to your project's actual setting.
Can I convert several rem values at once?
The tool converts one value at a time. If you need a whole spacing scale, run each value through in sequence and copy the results as you go.