Credit Card Processing Fee Calculator

Interchange-plus vs flat-rate: two different ways to price the same risk

Every card transaction has an underlying interchange fee -- set by the card networks (Visa, Mastercard, etc.) and paid to the card-issuing bank, varying by card type, rewards tier and how the card was entered, typically landing somewhere around 1.5% to 2.6%. An interchange-plus pricing model passes that real interchange cost straight through to you and adds a small, transparent markup on top (commonly a fraction of a percent plus a small fixed fee).

A flat-rate processor (like Stripe's or Square's standard pricing) instead charges one blended rate -- typically around 2.9% + $0.30 -- regardless of which specific card was used, absorbing the variation between a cheap debit card and an expensive rewards credit card into a single predictable number.

Which one is cheaper depends heavily on your actual card mix: a business that mostly sees basic debit cards can often save real money with interchange-plus, since the true interchange cost sits well below a flat rate's blended average, while a business that sees a lot of premium rewards cards may find a flat rate is effectively subsidized by simpler transactions and works out similarly either way.

Where these numbers come from

The formulas and default values in this calculator are based on:

• publicly published card network interchange rate ranges (commonly cited as roughly 1.5-2.6% depending on card type and entry method) and typical processor markups for interchange-plus pricing (commonly around 0.2-0.5% plus a small per-transaction fee)
• flat-rate figures reflect standard published rates from processors like Stripe and Square (approximately 2.9% + $0.30). Note: actual interchange rates are set by card network and card-issuer schedules that change periodically and vary by exact card and transaction type
• this tool compares averages, not a specific card's real interchange category

Platform fee schedules change. These are planning estimates based on the most recently published rates -- always confirm the current fee schedule on the platform itself before relying on the exact number for a real payout.