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CSS Unit Converter / Clamp Generator

Convert px, rem, em, %, vw, and vh with configurable context, then generate fluid clamp() CSS for typography and spacing.

Input value

Enter a CSS length and pick the source unit.

Converted values

Ready

Converted from 16px with the current context.

CSS Units and Responsive Sizing Course

Learn practical CSS unit workflows: px, rem, em, %, vw, vh, root font-size context, clamp() fluid sizing, and debugging responsive layouts.

Course home

About this tool

DevCove CSS Unit Converter / Clamp Generator helps frontend developers convert design measurements into CSS units and generate fluid clamp() values for typography and spacing. Configure root, parent, and viewport context, preview results at common breakpoints, then copy CSS ready for your stylesheet.

How to use this tool

Use this tool when you are translating design specs into CSS units or building fluid typography and spacing:

  1. Switch to Unit convert when you need px, rem, em, %, vw, or vh equivalents for one value.
  2. Adjust root font-size, parent font-size, and viewport dimensions to match your design system or page context.
  3. Click any converted unit card to copy that value, or copy all units at once.
  4. Switch to Clamp generator when you need responsive font-size or spacing with min and max bounds.
  5. Choose font-size or spacing mode, set min/max px values, and define the viewport range.
  6. Copy plain CSS, a custom property, or an SCSS variable, then review the preview bars at key viewport widths.
  7. Load the 16px → rem or fluid heading example when you want a realistic starting point.

Features

Built for frontend layout, design handoff, and responsive CSS delivery workflows:

  • Single-value conversion across px, rem, em, %, vw, and vh.
  • Configurable root font-size, parent font-size, and viewport width/height.
  • Fluid clamp() generator for typography and spacing.
  • Font-size and spacing preview modes with live size bars.
  • Copy CSS, CSS custom properties, or SCSS variables.
  • Built-in px/rem and fluid heading examples.
  • Client-side processing: your values stay in the browser and are not uploaded to DevCove servers.
  • Clear boundaries: no Tailwind config export, Figma parsing, or full design-system generation in the first version.

FAQ

Does this CSS unit converter upload my values?

No. All conversions and clamp() generation run locally in your browser after the page loads. Your input is not uploaded to DevCove servers.

Which CSS units are supported?

The first version supports px, rem, em, %, vw, and vh. Conversions use the root font-size, parent font-size, and viewport dimensions you configure in the toolbar.

How does the clamp() generator work?

You provide minimum and maximum sizes in px plus a viewport range. The tool computes a fluid clamp() expression with rem and vw terms, then previews the computed size at the minimum, midpoint, and maximum viewport widths.

When should I change root or parent font-size?

Use root font-size when converting px to rem or em for document-level sizing. Use parent font-size when converting em values inside a nested component whose font-size differs from the root.

Can I copy results for SCSS or CSS variables?

Yes. The clamp generator can copy plain CSS, a CSS custom property, or an SCSS variable so you can paste the result into your stylesheet workflow.

Why do vw/vh results change when I edit viewport width or height?

vw and vh are relative to the viewport. The tool uses your configured viewport dimensions as the conversion context, so updating those fields recalculates the equivalent px, rem, and em values.