Chrome DevTools Extension

Figma to Code Style Diffing

Catch visual discrepancies between Figma designs and actual browser rendering. Compare computed styles against Figma Dev Mode CSS with tolerance-aware diffing and severity classification.

figma-css-diff panel
// Comparing .card-title

font-size
Figma: 14px    Browser: 13.5px
⚠ minor (0.5px diff)

color
Figma: #1A1A1A    Browser: rgb(26, 26, 26)
✔ match (normalized)

padding-left
Figma: 24px    Browser: 16px
✘ major (8px diff)

Bridge Design and Implementation

Automatically detect style mismatches between Figma specs and your live pages, with smart normalization and configurable tolerances.

Visual Element Picker

Click to select any element on the page with a blue highlight overlay showing tag, classes, and dimensions. Or type a CSS selector directly.

Smart CSS Parsing

Paste CSS straight from Figma Dev Mode. Automatic shorthand expansion for padding, margin, border-radius, border, gap, and background.

Tolerance-Aware Diffing

Configurable thresholds classify mismatches as major, minor, or negligible. Subpixel rounding is auto-detected and annotated.

Style Normalization

Hex to RGB, rem to px, font-weight keywords, font-family extraction, and zero-unit stripping ensure accurate comparison regardless of format.

Batch Comparison

Compare up to 50 elements at once. Enter a selector matching multiple elements, paste multi-block Figma CSS, and get an accordion results view.

Report Export

Generate markdown-formatted diff reports with severity badges, match counts, and element info. One-click copy for PRs, Slack, or docs.

Quick Setup

Load the extension into Chrome in under a minute.

1. Clone the Repository

Download or clone the source code from GitHub.

git clone https://github.com/glorynguyen/ui-checker.git

2. Load in Chrome

Open chrome://extensions, enable Developer mode, click "Load unpacked", and select the chrome-extension folder.

1. Navigate to chrome://extensions/
2. Toggle "Developer mode" (top-right)
3. Click "Load unpacked"
4. Select the chrome-extension/ folder

What It Extracts and Compares

Automatically extracts 38 computed CSS properties from selected elements, covering 5 categories.

Category Properties Description
Spacing margin padding gap All directional margins, paddings, gap, row-gap, column-gap
Typography font-size font-weight color Font family, size, weight, line-height, letter-spacing, text alignment and transforms
Sizing width height min/max Width, height, min-width, max-width, min-height, max-height
Layout display flex position Flexbox direction, alignment, wrapping, positioning, and z-index
Visual background border shadow Background color, border width/style/color/radius, box-shadow, opacity, overflow
Variables var() fallback overrides CSS variable detection, inline override editor, saveable variable mappings with JSON export/import

How to Use

Open DevTools, find the "Figma CSS Diff" tab, and start comparing.

Single Element

Pick an element or enter a CSS selector. Paste the Figma CSS from Dev Mode. Click "Compare" to see color-coded results grouped by category with severity badges.

Batch Mode

Toggle Batch Mode, enter a selector matching multiple elements (e.g., .card), paste multi-block Figma CSS separated by /* label */ comments, and diff them all at once.

CSS Variables

Paste Figma CSS with var(--name, fallback) syntax. Click variable chips to override fallback values. Save overrides as named mappings and export as JSON for your team.