Currency Exchange Fee Highlighter

WHAT IT DOES

This script automatically scans any page for currency exchange fees, conversion charges, and foreign transaction costs, then highlights them with color-coded visual indicators—green for low fees, yellow for medium, red for high—based on your configured acceptable threshold. A floating overlay displays each detected fee rate alongside your threshold, showing you at a glance which fees are reasonable and which are excessive. The overlay also calculates the estimated cost of a sample transaction (default $100) for each fee, helping you understand the real-world impact. A floating badge shows the first detected fee and its status.

WHERE IT RUNS

The script works on any page with currency exchange information—banking websites, travel money sites, currency converter pages, international payment gateways, foreign transaction fee disclosures, and any page displaying percentage-based fees or charges. It detects fee patterns using regex for percentage values and related keywords (fee, charge, commission, conversion, exchange, foreign, transaction). The script works on any website regardless of framework.

HOW TO USE

After installation, the script automatically scans the page for exchange fees. A floating badge shows the first detected fee and its status (low, medium, or high). Click the badge to toggle the full overlay with all detected fees and estimated costs. Open the panel to customize: set the acceptable fee threshold (0-20%), configure the sample transaction amount, enable or disable the overlay and badge, choose overlay position (top-right, top-left, bottom-right, bottom-left), adjust opacity, select dark or light theme, set currency symbol, customize colors for low, medium, and high fees, and choose badge position. Click "Scan Now" to manually re-scan the page, or "Clear Highlights" to remove visual indicators.

TECHNICAL MECHANISM

The script uses a multi-stage fee detection pipeline. First, it scans the DOM for fee-related content using a comprehensive set of selectors (.fee, .charge, .commission, .conversion, .exchange, .rate, .currency) with fallback to text-based detection across common content containers. Second, it extracts fee values using multiple regex patterns that capture percentages in various formats (e.g., "2.5%", "Fee: 3.75%", "conversion 4.99%"). Third, it validates extracted fees to ensure they are within realistic ranges (0-100%) and deduplicates by label and value. Fourth, it classifies each fee by comparing it to the user-configured threshold: fees ≤ half the threshold are "low," fees ≤ the threshold are "medium," and fees above the threshold are "high." Fifth, it highlights matched elements with color-coded outlines and background tints using CSS classes. Sixth, it renders the overlay with fee details, status indicators, and estimated costs. Seventh, it displays a badge showing the first detected fee.

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. Fee detection relies on text pattern matching and may not capture all formats or miss fees in complex layouts. The script does not access, store, or transmit any personal data, financial information, or browsing history. All processing happens locally in your browser and never leaves your device.