Simplicity Web Pattern Size Chart Overlay

WHAT IT DOES

Simplicity Web Pattern Size Chart Overlay automatically scans Simplicity pattern product pages and extracts the complete size chart data, including bust, waist, hip measurements, and finished garment measurements for every available size. The tool displays a clean, readable size chart overlay panel directly on the product page, so you no longer need to hunt through product images or PDF downloads to find sizing information. You can enter your own body measurements into the panel, and the tool will highlight the recommended size based on the best match across all measurement points. The overlay supports both inches and centimeters, and remembers your preferred unit system along with your saved measurements across all your browsing sessions. This makes it easy to quickly determine the right pattern size for any Simplicity pattern you view, saving time and reducing the guesswork that often accompanies online pattern shopping.

WHERE IT RUNS

This extension operates exclusively on simplicity.com domain pages that contain product listings, specifically on individual pattern product pages. It works alongside the free BotGentz companion extension, which provides the necessary DOM access and page interaction capabilities. The size chart overlay runs entirely within your local browser instance and does not communicate with any external servers or APIs. All size chart extraction, measurement storage, and size recommendation logic occurs on your machine, ensuring your body measurements and shopping activity remain private. It supports all modern Chromium-based browsers (Chrome, Edge, Brave, Opera) and Firefox when paired with the BotGentz bridge.

HOW TO USE

After installing both BotGentz and this size chart overlay, simply navigate to any Simplicity pattern product page. Within 1-2 seconds, a panel appears in the bottom-right corner displaying the complete size chart for that pattern. The chart shows sizes along the left column and measurement categories across the top, with all data values clearly presented. Use the unit selector at the top of the panel to switch between inches and centimeters—all values will convert automatically. Enter your bust, waist, and hip measurements in the "Your Measurements" section. The panel will instantly highlight the recommended size in the chart and display a match confidence level. Your measurements are saved automatically and will be remembered the next time you visit any Simplicity product page. The "Clear Measurements" button removes all saved data. Use the panel to quickly compare sizes across different patterns and make informed purchasing decisions.

SIZE CHART EXTRACTION AND PARSING

The overlay uses a robust multi-strategy extraction system to locate and parse size chart data from Simplicity product pages. It first attempts to find the size chart using a comprehensive set of CSS selectors based on Simplicity's typical page structure, including class names like "size-chart," "size-guide," and "sizing-chart." When the primary selectors fail due to page updates, the tool scans for any table containing sizing-related content and analyzes its structure to identify size labels and measurement columns. It then applies a heuristic algorithm that determines which columns contain size labels (typically the first column) and which contain measurement data, automatically detecting whether values are in inches or centimeters. The tool also extracts measurement headers to label each data column appropriately. In cases where no table is present, the tool uses text-based parsing to find size indicators and numeric values, extracting as much structured data as possible. This multi-layer approach ensures reliable extraction across different product formats and page layouts.

THE PANEL

The size chart overlay panel is a compact, functional overlay that integrates into the Simplicity product page. It can be dragged by clicking and holding the title bar, positioning the panel anywhere on the screen for optimal visibility while you browse patterns. The panel includes a built-in snap feature that automatically aligns to the nearest screen edge when released within 48 pixels, keeping your workspace organized. Click the collapse arrow in the top-right corner to minimize the panel to a small icon bubble showing a gear emoji, preserving screen space while keeping the tool accessible. The panel is not resizable in this version, maintaining a consistent compact size that works on all screen resolutions. Press the Escape key to instantly hide the panel; press Escape again to restore it. All position, collapse state, preferred unit system, and saved measurements are stored locally using GM_setValue and persist across browsing sessions.

PLEASE NOTE

This extension requires the free BotGentz extension to function—the size chart overlay does not work standalone. Simplicity occasionally updates its product page layouts, which may temporarily affect size chart extraction accuracy. The tool extracts size data from the visible page content; if a product page does not display a size chart or uses a non-standard format, the overlay may not be able to display sizing information. Size recommendations are based on matching your entered measurements to the closest pattern size and are provided as guidance only—always verify pattern sizing with the official Simplicity size chart before purchasing. The tool does not store or transmit any data; all measurements and preferences are saved entirely within your browser. This tool is designed for personal shopping assistance and is not affiliated with or endorsed by Simplicity or its parent company. Pattern sizing may vary between collections; always consult the specific product page for accurate sizing.