Universal Bundle Discount Calculator

WHAT IT DOES

This script automatically detects bundle offers, multi-buy deals, and kit pricing on product pages, then calculates exactly how much you save compared to buying each item individually. A floating badge displays the total savings amount, discount percentage, and a per-item breakdown showing the individual prices and the combined bundle price. The script identifies "buy X get Y" deals, value packs, combo offers, and multi-item discounts, helping you instantly see whether a bundle is actually a good deal or just clever marketing.

WHERE IT RUNS

The script works on any product page across the web—Amazon, Walmart, Target, Best Buy, Costco, eBay, and thousands of other e-commerce platforms. It runs on any page that displays bundle offers, multi-item discounts, or kit pricing. The script's multi-pattern detection finds bundle information whether it's in dedicated bundle sections, product descriptions, promotion banners, or deal listings.

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 discount badge appears, choose its position (top-right, top-left, bottom-right, bottom-left), and set custom colors for discount and no-discount states. Toggle the per-item breakdown to see individual item prices, and optionally include tax in the comparison. 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 bundle detection and discount calculation pipeline. First, it locates bundle-related content using a prioritized selector strategy targeting common bundle elements (.bundle, .bundle-price, .bundle-offer, .multi-buy, .multibuy, .offer-bundle) with fallback to text-based keyword detection across product description containers. Second, it extracts bundle pricing using regex pattern matching for currency values, looking for the bundle price and any stated savings. Third, it identifies individual items within the bundle by scanning list items, product variants, and comma-separated lists within the bundle container. Fourth, it extracts each item's individual price and calculates the total individual value. Fifth, it computes savings as the difference between the individual total and the bundle price, and calculates the discount percentage. The script also handles "buy X get Y" deals by parsing quantity-based offers. Confidence levels are assigned based on data completeness—full price data yields high confidence.

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. Bundle detection relies on the specific text and HTML structure of each website, which may vary or change over time. The script provides helpful calculations but should not be relied upon for exact pricing—always verify bundle pricing and terms with the retailer before purchasing. The script does not access, store, or transmit any personal data, purchase history, or browsing information. All detection and calculation happens locally in your browser, and no information ever leaves your device.