MetoolzyCSS Unit Converter
16px1rem1em100%12pt0.8333vw6 Units
px, rem, em, %, pt, vw.
Custom Base
Set base font size and viewport width.
Copy Result
One-click copy to clipboard.
Client-side
All processing in your browser. No data uploaded.
About CSS Unit Converter
CSS Unit Converter helps front-end developers and designers translate measurements between the six most common CSS length units: px (pixels), rem (root em), em (local em), % (percent), pt (points), and vw (viewport width). Getting unit conversions right is critical for responsive layouts — a spacing value that looks perfect at a 1440px viewport can break completely at 375px if the units are not chosen carefully. rem and em are preferred for typography because they scale with the user's browser font size preference, improving accessibility; vw adapts to viewport width for fluid layouts; and px remains useful for borders and fine details that should not scale. Enter any value, pick its unit, and see all six equivalents computed simultaneously. You can also customise the base font size (default 16px) and viewport width for accurate context-specific conversions.
How to Use CSS Unit Converter
- Type the numeric value you want to convert into the left input field.
- Select the source unit from the dropdown (px, rem, em, %, pt, or vw).
- If needed, update the "Base font" field — this affects rem, em, and % calculations. The default is 16px.
- If needed, update the "Viewport" field — this affects vw calculations. The default is 1920px.
- All six unit equivalents update instantly in the grid below.
- Click any result card to copy that value (with its unit suffix) to the clipboard.
Frequently Asked Questions
What is the difference between rem and em?
rem (root em) is always relative to the root element's font size (typically 16px). em is relative to the font size of the element itself, which can cascade and compound in nested elements.
Why does % conversion depend on the base font size?
In the context of font sizes, percentage values are relative to the parent element's font size. This tool uses the base font size as a stand-in for the parent, giving a useful approximation.
How many pixels is 1 point (pt)?
1pt = 96/72 ≈ 1.333px at standard screen resolution. Points are a print measurement unit and rarely used in modern CSS.
What viewport width should I enter?
Use the target device width for your design. Common values: 375px (iPhone SE), 768px (tablet), 1440px (desktop), 1920px (wide desktop).
Can I convert multiple values at once?
Currently the tool converts one value at a time. For batch conversions, use your browser's DevTools console with a custom script.
Related Tools
Top 10 Free Tools Every Developer Needs
Boost your productivity instantly. Get our exclusive cheatsheet featuring the most essential web utilities you didn't know you needed, delivered straight to your inbox.
We respect your inbox. Unsubscribe at any time.
The Ultimate CSS Unit Converter
CSS Unit Converter is a powerful, free online tool designed to simplify your digital workflow. Convert between CSS units: px, rem, em, %, pt, vw.
In today's fast-paced digital world, efficiency is key. Whether you're a developer, designer, or digital marketer, finding reliable utilities is crucial. With our CSS Unit Converter, you can get things done instantly right in your browser, with absolutely no signup required.
Why Use Our CSS Unit Converter?
Our tool is built with performance and privacy in mind. All processing is incredibly fast, ensuring you don't waste any time.
- 100% Free: No hidden fees or premium paywalls.
- No Installation: Works instantly in any modern web browser.
- Privacy First: We respect your data. Most processing happens directly on your device.
- User-Friendly: A clean, intuitive interface that anyone can use without technical skills.
How it benefits your workflow
Integrating the CSS Unit Converter into your daily routine saves you valuable time. Instead of downloading bulky software or writing custom scripts, you can bookmark this page and solve your problem in just a few clicks.
Try it out today and experience the easiest way to handle your tasks!
Top 10 Free Tools Every Developer Needs
Boost your productivity instantly. Get our exclusive cheatsheet featuring the most essential web utilities you didn't know you needed, delivered straight to your inbox.
We respect your inbox. Unsubscribe at any time.