Universal Out-of-Stock Notifier

WHAT IT DOES

This script automatically scans product pages for stock status—In Stock, Out of Stock, Pre-Order, or Backorder—and displays a clear, color-coded badge with the current status. When an item is out of stock, the script continues monitoring the page and will alert you the moment it comes back in stock. The badge shows the stock status, confidence level, and any available restock date. Visual and optional sound notifications ensure you never miss a restock, so you can be the first to purchase high-demand items before they sell out again.

WHERE IT RUNS

The script works on any product page across the web—Amazon, Best Buy, Walmart, Target, Newegg, and thousands of other e-commerce sites. It runs on any page that displays stock availability information, regardless of where that information is located. The script's multi-pattern detection finds stock status even when it's buried in product descriptions, shipping sections, or dynamic modal dialogs.

HOW TO USE

After installation, the script scans automatically when you load a product page. Open the panel to customize your experience: toggle auto-scan on or off, control whether the stock badge appears, choose its position, set custom colors for each stock status, and enable or disable restock alerts, desktop notifications, and sound alerts. Click "Scan Now" to manually trigger a scan after dynamic content loads. Click the badge itself to toggle its opacity for a less distracting view. All settings are saved and persist across pages.

TECHNICAL MECHANISM

The script uses a multi-stage stock detection pipeline with continuous monitoring. First, it locates stock status containers using a prioritized selector strategy targeting common stock elements (.stock-status, .availability, .product-availability, .stock, .in-stock, .out-of-stock) with fallback to text-based keyword detection. Second, it classifies status using regex pattern matching on the element's text content, checking for "out of stock," "sold out," "pre-order," "backorder," and "in stock" patterns. Third, it extracts restock dates using date pattern recognition. Fourth, it stores the current status in GM_setValue and compares it against previous scans to detect changes. Fifth, it uses a MutationObserver to watch for DOM changes on stock elements and a periodic timer to re-check status at configurable intervals. When a change from out-of-stock to in-stock or pre-order is detected, the script triggers notifications and flashes the badge.

THE PANEL

The settings panel is fully draggable and can be positioned anywhere on your screen. It automatically snaps to the nearest edge when released, keeping your workspace organized. The panel can be collapsed to a small bubble showing only a gear icon, and restored with a single click. Its position is remembered across page reloads using GM_setValue. The panel also responds to the Escape key, which instantly hides it until you click the bubble again. All settings are saved immediately when changed and persist across browser sessions.

PLEASE NOTE

This script requires the free BotGentz extension to run. Stock status detection relies on the specific text and HTML structure of each website, which may vary or change over time. The script provides helpful alerts but should not be relied upon for critical restock monitoring—always verify stock availability with the retailer directly before purchasing. The script does not access, store, or transmit any personal data, purchase history, or browsing information. All detection and monitoring happens locally in your browser, and no information ever leaves your device.