MCC Displayer

MCC Displayer shows you the Merchant Category Code (MCC) when you reach the payment step on checkout pages. MCCs are 4-digit codes that classify businesses by their primary activity - they determine how your credit card rewards are calculated, whether cashback applies, and how transactions appear on your statement. Why It Matters - Credit Card Rewards: Many cards offer bonus rewards for specific MCC categories (e.g., 3x points on dining, 5% back on groceries) - Expense Tracking: Know how your purchase will be categorized before you complete it - Business Expenses: Verify merchant classifications for expense reports and tax purposes Key Features Smart Detection - Automatically detects when you're on a payment step (card entry forms, saved payment methods) - Works with major payment providers including Stripe, PayPal, Square, Braintree, and Adyen - Supports single-page applications with real-time updates Intelligent MCC Resolution - Domain-specific rules for accurate classification - Flow-based detection for multi-purpose sites (e.g., distinguishes between flights vs. hotels on travel sites) - Heuristic fallback for unknown merchants Customizable - Set manual overrides for specific domains - Adjustable auto-close timer for the notification badge - Import/export rules for backup and sharing Privacy-Focused - All processing happens locally in your browser - No data is sent to external servers - No account required How It Works 1. Browse to any checkout page 2. When you reach the payment step, a badge appears showing the MCC 3. Hover over the badge for details (category, confidence level, detection source) 4. Click to access more options or dismiss Perfect For - Credit card rewards optimizers - Small business owners tracking expenses - Anyone curious about how merchants are classified