PX to REM for Web Development

Convert pixel values to rem units for scalable, accessible CSS. Set your base font size and instantly see all equivalent values.

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From

1rem

Context (affects rem/em/vw/vh/%)

Root font (px)

Parent font (px)

Viewport W (px)

Viewport H (px)

All conversions for 16 px

Root EM (rem)1 rem

EM (em)1 em

Points (pt)12 pt

Viewport Width (vw)1.11111 vw

Viewport Height (vh)1.77778 vh

Percent (%)100 %

Common pixel sizes → rem (at 16px base)

Web Dev tips

🌐

REM units scale with the user's browser font size setting. Using rem instead of px makes your site accessible to users who set larger default text sizes.

💡

Most browsers default to 16px base. That means 1rem = 16px, 1.5rem = 24px, 2rem = 32px. The reference table at the bottom shows common conversions at a glance.

📐

Using rem for font sizes and em for component-level spacing is a common best practice — em respects the local context, rem stays anchored to the root.

🎨

Tailwind CSS uses a 16px base. Its spacing scale (text-sm = 0.875rem = 14px, text-base = 1rem = 16px) is visible in the common sizes reference below.