Merchant Discount Rate Calculator

Several factors influence your merchant discount rate: your card mix (debit vs credit vs rewards vs Amex), processing method (swiped, dipped, tapped, keyed, e-commerce), average transaction size, monthly processing volume, business industry/risk category, and your payment processor pricing model. Interchange rates vary by card type - rewards cards generally have higher interchange rates than debit cards.

Interchange fees are set by the card networks and paid to the card-issuing bank. These fees vary by card type (debit, standard credit, rewards, premium), processing method (card-present typically has lower rates), and transaction details. Interchange typically makes up 70-90% of your total MDR. Our merchant discount rate calculator includes default interchange rates based on your selected card mix and processing method.

A blended MDR (or effective MDR) is the average merchant discount rate across all your transactions, weighted by the volume and value of each card type you accept. It combines the different interchange rates for debit, standard credit, rewards, and Amex transactions with your network assessment fees and processor markup. The blended MDR gives you a single, understandable rate that reflects your actual processing cost.

To lower your MDR, consider: encouraging debit or standard credit card usage over rewards/premium cards, using EMV chip or contactless methods instead of keyed entry, negotiating with your processor for lower markup, ensuring you meet monthly volume thresholds to waive minimum fees, enabling address verification (AVS) and CVV checks for card-not-present transactions, and reviewing your processor statement to identify any unnecessary fees.

Absolutely. All calculations in our merchant discount rate calculator are performed locally in your browser using JavaScript. None of your transaction data - including volume amounts, card mix percentages, or fee details - is ever sent to any server or stored anywhere. Your financial information stays entirely on your device, ensuring complete privacy and security.

Interchange-plus pricing charges the actual interchange rate plus a fixed processor markup (e.g., interchange + 0.10% + $0.10), which is generally more transparent and cheaper for most businesses. Flat-rate pricing charges a single blended rate (e.g., 2.6% + $0.10) regardless of card type. Our calculator supports both models, showing you the effective MDR under each pricing structure.

Monthly minimums increase your effective MDR when your actual processing costs fall below a minimum threshold. For example, if your total monthly fees are $20 but your processor has a $25 monthly minimum, you pay $25 - effectively raising your MDR for that month. Our merchant discount rate calculator accounts for this by projecting whether the minimum will apply to your monthly volume.