🚀 Wow1

CSS Unit Converter

Convert between px, rem, em, vw, vh, pt, cm and more

From Value
To Value
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How to Use

  1. 1 Enter a value in the first input field
  2. 2 Select the source unit (e.g., px)
  3. 3 Select the target unit (e.g., rem)
  4. 4 The converted value appears instantly
  5. 5 Click copy to use the result in your CSS

What You Get

CSS unit converter supporting 13 units including px, rem, em, vw, vh, vmin, vmax, %, pt, pc, cm, mm, and inches. Features bulk CSS converter, reference table, and viewport presets for responsive design.

Input: 16px

Output: 1rem (with 16px base font size)

Input: 24px

Output: 1.5rem

Input: 100vw on 1920px viewport

Output: 1920px

How do I convert px to rem in CSS?

Divide the pixel value by the root font size (usually 16px). For example, 24px ÷ 16 = 1.5rem. Our converter does this automatically – just enter your px value and select rem as the target unit.

What is the difference between rem and em in CSS?

rem is relative to the root (html) font size, while em is relative to the parent element's font size. rem is more predictable since it always refers to the same base size. Use rem for consistent sizing across your entire website.

Why should I use rem instead of px?

rem units respect user browser settings for font size, making your site more accessible. When users change their browser's default font size, rem-based layouts scale appropriately while px stays fixed.

What does 1rem equal in pixels?

By default, 1rem equals 16px because most browsers have a default font size of 16px. However, this can change if the root font size is modified in CSS or by user preferences.

How do I convert px to vw for responsive design?

Divide the pixel value by the viewport width and multiply by 100. For a 1920px viewport: 192px ÷ 1920 × 100 = 10vw. Our converter handles this calculation – just set your viewport width in settings.

What is the best CSS unit for responsive design?

Use rem for typography and spacing (accessibility), vw/vh for full-width/height sections, and % for flexible containers. Avoid px for font sizes. A combination of units works best for truly responsive designs.

How many pixels is 1 inch in CSS?

1 inch equals 96 pixels in CSS. This is a fixed ratio defined by the CSS specification, regardless of actual screen DPI.

Can I convert my entire CSS file from px to rem?

Yes! Use our Bulk Converter tab. Paste your CSS code, select px → rem, and get the converted CSS instantly. All px values are replaced while other units remain unchanged.

100% client-side processing. Your CSS code never leaves your browser.