PX to REM Converter
Pixels to rem/em and back for CSS.
Tool inputs stay in your browser · optional AI search sends your query
How to use it (step by step)
- 1Fill in the boxes: “Value”, “From”, “Root font size”. Example numbers are already there so you can see how it works; replace them with yours.
- 2The result updates instantly as you type (on a phone it is below the boxes).
- 3The bold line is the main answer. Tap Copy next to any value to copy it.
Words to know
- Resolution / pixels
- A picture is made of tiny dots called pixels. 1080×1920 means 1,080 dots wide and 1,920 tall.
- Unit conversion
- Changing a value from one measurement to another, like kilometers to miles. The amount stays the same; only the unit changes.
- CSS
- The code that controls how a web page looks: colors, sizes, spacing and layout.
- Logarithm / root
- A root undoes a power (the square root of 9 is 3). A logarithm asks “what power gives this number?” (log₁₀ 100 = 2).
More in Design & Color
Black & White Stencil MakerConvert image pixels into a two-tone stencil at your chosen cutoff.Ordered Dithering Image ToolCreate a black-and-white retro image using a 4×4 Bayer pattern.Image PosterizerReduce the number of color levels in actual image pixels.Image Color ReplacerReplace matching colors in a graphic while retaining transparency.Sprite Sheet & Grid SlicerSplit any regular image grid into numbered PNG files and a ZIP.Image Difference HeatmapCompare two same-size images and export a visible difference map.