CSS Unit Converter (px ↔ rem ↔ em)

Convert CSS units between px, rem, and em using a configurable base font size. Copy results instantly.

CSS Unit Converter (px ↔ rem ↔ em) is a lightweight Chrome extension that helps users quickly convert CSS length units between pixels (px), rem, and em. By entering a numeric value, selecting the source unit, and defining a base font size, users can instantly see accurate conversion results. The extension also provides a quick overview of the converted value in all three units at the same time, making it easier to compare and understand how different CSS units relate to each other. All calculations are performed locally within the browser, with no data collection, no external requests, and no special permissions required. This tool is useful for front-end developers, designers, and learners who work with responsive typography and layout sizing. The interface is focused, simple, and efficient, allowing fast conversions directly from the Chrome toolbar without any setup or configuration.