The true cost of Stripe fees: a calculator for SaaS

Stripe’s advertised card rate is 2.9% + $0.30 per successful charge — but that’s the floor, not what you actually pay. International cards add roughly 1 percentage point, currency conversion adds another, and both stack on top of each other across your real transaction mix. Enter your own numbers into the calculator below and it computes your blended rate and dollar cost, with the formula shown inline so you can check it by hand.

What Stripe actually charges

Stripe’s standard published US pricing, as of 2026-10-04 (source: stripe.com/pricing), is:

• 2.9% + $0.30 per successful domestic card charge
• +1 percentage point for international cards
• +1 percentage point for currency conversion

These are list-price figures, not universal. Stripe negotiates lower interchange-plus rates for higher-volume accounts, and pricing varies by country and by plan. Treat the numbers above as a starting point and confirm your actual rate in your own Stripe Dashboard — the gap between “list price” and “what you’re actually billed” is exactly the thing worth checking before you trust a back-of-envelope estimate.

Calculate your real Stripe cost

Fill in your own revenue and transaction mix. Nothing here is sent anywhere — it’s plain JavaScript running in your browser, computing the formula above against your numbers.

function recalc() { var revenue = Math.max(0, parseFloat(els[“sfc-revenue”].value) || 0); var avgTxn = Math.max(0.01, parseFloat(els[“sfc-avg-txn”].value) || 0.01); var intlPct = clamp(parseFloat(els[“sfc-intl”].value) || 0, 0, 100); var fxPct = clamp(parseFloat(els[“sfc-fx”].value) || 0, 0, 100);

var baseRatePct = 2.9;
var effectiveRatePct = baseRatePct + (intlPct / 100) + (fxPct / 100);
var numTransactions = revenue / avgTxn;
var monthlyPercentFee = revenue * (effectiveRatePct / 100);
var monthlyFixedFee = numTransactions * 0.30;
var monthlyFeeCost = monthlyPercentFee + monthlyFixedFee;
var blendedRatePct = revenue > 0 ? (monthlyFeeCost / revenue) * 100 : 0;
var annualFeeCost = monthlyFeeCost * 12;

rateOut.textContent = fmtPct(blendedRatePct);
monthlyOut.textContent = fmtUSD(monthlyFeeCost);
annualOut.textContent = fmtUSD(annualFeeCost);

}

for (var j = 0; j < ids.length; j++) { var el = els[ids[j]]; if (el) el.addEventListener(“input”, recalc); } recalc(); })();

With the defaults above — $50,000/month revenue, $500 average transaction, 20% international cards, 10% needing currency conversion — the blended rate comes out to about 3.26%, or roughly $19,560/year in processing fees. Change any input and the numbers recompute instantly; none of it leaves your browser.

Why the real number is higher than 2.9%

The gap between the headline rate and your real bill comes from stacking, not from any single hidden fee. International cards and currency conversion are each separate 1-point surcharges, and they apply independently to whatever share of volume triggers them — so a business with a lot of cross-border customers can easily see a blended rate 20-40% higher than the 2.9% figure on Stripe’s homepage, before the flat $0.30 per transaction is even added in. The fixed $0.30 matters most at low average transaction sizes: at a $10 average transaction, $0.30 alone is 3% of the charge, on top of the percentage rate.

One anecdote — not a statistic

A Reddit thread (frequently cited, several hundred upvotes, not independently verified here) put one high-volume international SaaS’s annual Stripe cost at roughly $17,400/year. That number is worth noting as color — it’s the kind of bill that prompts someone to actually do the math — but it’s a single unverified anecdote about one company’s specific mix, not a benchmark for yours. The calculator above uses your own revenue and transaction mix instead of borrowing someone else’s story.

What to do with the number

If your blended rate is meaningfully above 2.9%, a few levers are worth checking before accepting it as fixed cost: ask Stripe about interchange-plus pricing once you have enough volume to negotiate, see whether a meaningful share of “international” charges are actually from customers who’d pay in their local currency if you offered it (removing the conversion surcharge on those), and check whether batching or minimum-charge rules make sense for unusually small transactions where the flat $0.30 dominates the percentage fee. None of these change Stripe’s published rate card — they change how much of your volume is exposed to the surcharges on top of it.

If you’re also looking at where SaaS costs quietly compound beyond the sticker price, see the Adobe Tax on how PDF tooling defaults to recurring billing for occasional work.