Pure Frontend · Custom Property Extraction · Auto-Grouping · Unused Detection · Multi-Format Export
Zero Dependencies · Works OfflineWhat Can the CSS Variable Extractor Do?
The CSS Variable Extractor is a pure frontend online tool for extracting all custom properties (CSS Custom Properties, i.e., variables starting with --) from CSS code. It automatically parses CSS, identifies variable definitions and references, groups them by color, spacing, font, border, and other categories, detects unused variables, and supports export to CSS custom properties, SCSS variables, JSON design tokens, and Tailwind configuration. All parsing is done locally in your browser—no code is ever uploaded to any server.
Core Features
- Smart Extraction: Automatically identifies all
--variable-namedefinitions, including those in :root, body, and any selector - Auto-Grouping: Intelligently categorizes variables by color, spacing, font, border, shadow, animation, etc.
- Unused Detection: Compares var() references to flag variables that are defined but never used
- Color Preview: Automatically detects color value variables and displays color swatches
- Multi-Format Export: CSS custom properties, SCSS variables, JSON design tokens, Tailwind configuration
How to Use
Step 1: Paste CSS code in the input box, drag-and-drop a .css file, or click "Load Example".
Step 2: Click "Extract Variables" or press Ctrl+Enter to automatically parse and display all variables.
Step 3: View the grouped variable list with color swatches for color variables and red flags for unused ones.
Step 4: Select an export format (CSS/SCSS/JSON/Tailwind) and click "Copy" or "Download" to save results.
Use Cases
Design System Building
Extract design tokens from existing CSS to build a unified design variable system and ensure design consistency.
Code Audit
Discover unused CSS variables, clean up redundant code, and reduce CSS file size.
Technology Migration
Migrate CSS custom properties to SCSS variables or Tailwind configuration for different tech stacks.
Theme Development
Extract all color and spacing variables to quickly create dark/light theme variants.
Technical Background
CSS Custom Properties start with -- and are referenced via var(--name). Unlike preprocessor variables, CSS custom properties are runtime variables that support cascade, inheritance, and JavaScript dynamic modification. Naming conventions recommend --category-property-variant format, e.g., --color-primary-500, --spacing-md. Design Tokens are the practice of abstracting design decisions into reusable variables, and CSS custom properties are the native Web standard for implementing design tokens.
FAQ
Which CSS variables can be extracted?
Extracts all CSS custom properties (variables starting with --), including those defined in :root, body, and any selector, as well as variables referenced via var().
Is grouped export supported?
Yes. Auto-groups by color, spacing, font, border, etc. Export to JSON, SCSS variables, CSS custom properties, and more.
Is data uploaded to a server?
No. All CSS parsing and variable extraction is performed locally in your browser. Code never leaves your device.
Can it detect unused variables?
Yes. The tool checks which variables are referenced via var() and marks those that are only defined but never used.
Does it support drag-and-drop CSS files?
Yes. Drag a .css file directly into the input area to load and analyze it.
What export formats are available?
Export as CSS custom properties, SCSS variables ($name), JSON design tokens, or Tailwind configuration.
Feedback: dexshuang@google.com