CSS Unit Converter

Convert values between px, rem, em, vw, and vh.

Processed locally

This tool runs in the browser.

Value

Source Unit

Root Font Size (px)

Base 1rem font size.

Viewport Width (px)

Reference for 100vw.

Viewport Height (px)

Reference for 100vh.

Pixels (px)

16px

Root EM (rem)

1rem

Element EM (em)

1em

Viewport Width (vw)

0.8333vw

Viewport Height (vh)

1.4815vh

About CSS Units

Pixels (px) provide absolute lengths on screens.

Root EM (rem) scales relative to the HTML root font size. It improves accessibility.

Viewport Width (vw) and Viewport Height (vh) calculate lengths relative to browser window dimensions.