Shopping Cart Total Tracker

WHAT IT DOES

Shopping Cart Total Tracker is a browser extension that scans any webpage for shopping cart details including total, subtotal, tax, shipping, and item count. It displays a summary of cart details in a floating panel, calculates the total including tax and shipping, and highlights if the total changes. You can quickly copy the total amount to your clipboard with one click. The tool is ideal for online shoppers who want to monitor their cart totals across different shopping sites, compare prices, or keep track of their spending during checkout.

WHERE IT RUNS

Shopping Cart Total Tracker runs on any webpage, overlaying a floating panel that does not interfere with page content. It operates entirely in your browser as a lightweight userscript, scanning the page for price and cart-related text. It works on any page, whether static or dynamic, with no external dependencies. All settings are stored locally using GM_setValue—no data is ever sent to any server.

HOW TO USE

After installation, open the floating panel by clicking the extension icon. The panel shows the current status (Enabled or Disabled) and a toggle button to enable or disable the tracker. The panel automatically scans the page for cart data and displays a summary with the total amount prominently shown. Below the total, you can see subtotal, tax, shipping, and item count if detected. Click the "Copy Total" button to copy the total amount to your clipboard. Click the "Scan Cart" button to manually rescan the page. The tool automatically rescans when the page content changes. All settings are saved per website.

REAL MECHANISM — WHY THIS WORKS

Most shopping cart tracking tools require manual inspection of the page source or using external bookmarklets that may not work on all sites. Shopping Cart Total Tracker uses a DOM-scanning approach that directly reads price and cart-related text from the page. The tool traverses the DOM using a TreeWalker to find text nodes containing currency patterns or price formats. It then uses pattern matching to identify common cart-related labels: "subtotal," "total," "tax," "shipping," and item counts. The tool extracts numeric values using regular expressions, detects currency symbols ($, €, £, ¥, etc.), and calculates the total by combining subtotal, tax, and shipping when the total is not explicitly shown. The tool also tracks changes in the total amount and highlights differences. A MutationObserver detects dynamically added content and rescans automatically. This approach ensures accurate, real-time, and fully private shopping cart tracking without requiring any external services or network access.

THE PANEL

The floating panel is fully draggable and remembers its position per site, snapping to the edges of the viewport when dragged near them. You can collapse the panel to a small icon to minimize screen distraction and expand it back with a single click. The panel is resizable from the bottom-right corner, giving you more space to view cart details. Press the Escape key to close the panel instantly. The panel remains open across page navigation within the same domain, maintaining your current view state. All preferences—panel position and enabled state—are saved per domain for a seamless experience.

PLEASE NOTE

Shopping Cart Total Tracker requires the free BotGentz extension to be installed and enabled, as it relies on the cross-extension messaging API provided by BotGentz for DOM access permissions. The tool scans for text patterns and may not detect cart data on all websites, especially those with complex or dynamic cart implementations. The tool does not modify page content or interact with checkout forms. The total calculation is a best-effort estimate; always verify the final total on the checkout page. All settings are stored locally in your browser using GM_setValue. No shopping data, page content, or usage information is ever sent to any server. The extension does not read, store, or transmit any personal information. It only scans and displays cart data at your request.