PX to REM Converter

Convert Any CSS Unit to Every Other One

Type a value in px, rem, em, pt, %, or a viewport unit (vw, vh, vmin, vmax) and see the exact equivalent in all of them at once. The math pivots through the CSS reference pixel, so the numbers match what the browser actually renders — not a rounded lookup table.

What makes this reliable is that you control the reference. rem depends on your root font-size, em and % depend on the parent font-size, and viewport units depend on the viewport dimensions. Set those to match your project (or click "Use my screen size") and every conversion is correct for your context, not a generic 16px assumption. Click any result to copy it with its unit.

Common Use Cases

• px to rem for accessible type: Convert a design handed to you in pixels into rem so it scales with the user's browser font-size setting.
• The 62.5% root trick: Set the root font-size to 10px and read rem values as clean tenths (1.6rem = 16px) without doing the division in your head.
• Points from a print or Figma spec: Turn a 12pt or 14pt type size into the px value CSS expects (1pt = 1.333px at 96dpi).
• Fluid layouts: Check what a px width becomes in vw at 1920, 1440, or your own viewport before writing a clamp() or media query.
• em nesting sanity checks: See how a value behaves when the parent font-size isn't the default 16px, so nested em values don't surprise you.
• Design-to-code handoff: Paste one number and copy the whole set of equivalents to drop straight into a stylesheet or a comment.

Privacy: This runs entirely in your browser with plain JavaScript math. Nothing is uploaded, there is no signup, and no value you enter ever leaves your device.