# CSS Size converter

> A simple and handy extension to convert CSS sizes PX, EM, and REM

Canonical page: [https://chrome-stats.com/d/css-size-converter](https://chrome-stats.com/d/css-size-converter)

## Overview

- **ID:** `css-size-converter`
- **Platform:** Firefox
- **Type:** Firefox add-on
- **Status:** Available
- **Publisher:** RMK
- **Category:** web-development
- **Daily users:** 1
- **Version:** 1.0.0
- **Last updated:** 2021-01-19
- **First published:** 2021-01-18
- **Size:** 658 KB
- **Data as of:** 2026-09-09
- **Store listing:** [Firefox Add-ons Store](https://addons.mozilla.org/firefox/addon/css-size-converter/)

## Description

CSS Size converter is a useful Firefox add-on for web developers who use mockups like Figma and Adobe XD. It allows for quick conversion of CSS sizes between PX, EM, and REM units, eliminating the need for manual calculations.

## Rankings

- #113,639 — Overall

## Safety

- **Risk impact:** Very low risk impact
- **Risk likelihood:** Moderate risk likelihood

### Analysis details

- This permission has no access or impact on the user's system or data, thus carrying no risk.
- This extension has low user count. Unpopular extensions may not be stable or safe.

> Some risk analysis details are omitted from this free response. [Upgrade to view the full analysis](https://chrome-stats.com/pricing).

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Source: [Chrome-Stats](https://chrome-stats.com/d/css-size-converter)