A free tool that tells small business owners what card processing actually costs them — built by someone who doesn’t sell card processing.
Almost every small business owner can tell you the rate they were quoted. Very few can tell you the rate they actually pay.
Those are different numbers, and the gap between them is where the money goes. Quoted rates describe one kind of transaction under ideal conditions. What you actually pay includes downgrades, per-item charges, monthly fees, gateway fees, PCI fees, and line items with names nobody explains. Divide total fees by total sales and the result is frequently a full percentage point above the number you agreed to — sometimes several.
The reason this stays hidden is not complexity. It is that almost every resource explaining card processing is paid by someone selling card processing. Comparison sites earn referral commissions. Calculators are lead-capture forms. Statement analysis software is sold to sales agents so they can pitch you faster. The information exists; it is just never free of the interest of whoever is handing it to you.
Know The Rate is an attempt at the other thing: work out the number, show the arithmetic, name the assumptions, and sell nothing.
It doesn’t. Not yet, and not in any of the usual ways for this category.
Square and Stripe are named on the calculator because their pricing is public and checkable, which makes the comparison verifiable. There is no relationship with either company, no commission if you sign up with them, and naming them is not a recommendation.
This site recommends no processor, ranks no provider, and takes no money from any payments company. That rule exists because the person behind it works in software sales for a company whose products touch payments — so you never have to wonder whether a recommendation here was paid for. There aren’t any.
In practice that means no “best processor” list, no rankings, no referral links, and no provider put forward as a suggestion. Where a named company does appear — Square and Stripe on the calculator — it is as a published price to measure against, because their pricing is public and anyone can check it. Naming them is not endorsing them.
The work here is translation, not brokerage. Nothing on this site can be bought, and nobody here gets paid when you sign something.
The calculator shows three figures on one scale.
Your total fees divided by your gross card sales for the same month. This is your effective rate, and it is your own arithmetic — no assumptions involved.
The base cost of accepting the card. Most of it is interchange, which goes to the bank that issued your customer’s card; the rest is assessment fees, which go to Visa and Mastercard. This is what the transaction costs before any processor adds a markup. It is modelled from published Visa and Mastercard schedules, blended 60/40 by volume, using an assumed mix of debit, standard credit and rewards cards based on your business type. This bar is an estimate, and the card mix is the largest source of error in it. American Express is excluded, because its pricing is not reliably published.
Paying above base cost is normal and necessary — no processor works for free. A markup of roughly 20 to 50 basis points is a competitive deal. The base-cost figure is a floor, not a target.
What your sales would cost on public, no-negotiation pricing from a named provider. Taken directly from their published pricing pages and applied to your numbers.
Enter card sales only — gross sales through your processor, not cash or checks. Including cash will make your rate look better than it is.
And if your processor deducts fees from each day’s deposit rather than billing you monthly, or splits one month’s charges across two statements, the “total fees” line on a single statement understates what you actually paid. If that sounds like your arrangement, the result here will read low.
Interchange changes roughly every April and October, and flat-rate pricing drifts without announcement. Everything here is re-checked on that cadence and the review date above is updated when it happens. If that date is more than six months old, treat the base-cost figure with suspicion.
If a number here is wrong, it should be fixed rather than defended. Rates change, sources conflict, and assumptions age. Corrections are welcome and will be made with the date noted.
If a figure looks wrong, or your statement says something this tool didn’t expect, send it. Statements are the most useful thing anyone can share — they are how the estimates here get better, and how the fee names nobody explains get documented in the first place.