Published online rates
- Stripe — 2.9% + $0.30 per successful card charge on Stripe US pricing. No monthly fee on the standard US pricing table CardFeeCalc uses.
- Square — on Square US pricing, the Online API processing row is 2.9% + $0.30 (Online API card payments, every Square plan) on Free, Plus, and Premium. Square Free also lists card payments made online or through an invoice at 3.3% + $0.30 (Square Free, online or invoice card) ($0/mo. per location on the Free plan). Examples and the embed below use that Online row so they match /square and /compare.
- PayPal Checkout — 3.49% + $0.49 (PayPal Checkout, Guest Checkout, and Venmo) on PayPal US business fees. Higher fixed fee than Stripe; compare micropayments and in-person tables only if those are how you actually get paid.
Monthly fees and hardware (context only)
Stripe’s US pricing page lists pay-as-you-go processing without a monthly platform fee for the standard online rate above. Square’s pricing page shows optional Plus ($49/mo.) and Premium ($149/mo.) plans with lower online and in-person percentages. Worked examples use Square Free card payments made online or through an invoice (3.3% + $0.30), not the 2.9% + $0.30 Online API row—change the Square calculator if your plan or payment path differs. PayPal Checkout does not add a separate monthly line item on the US business fees table for the Checkout rate modeled here—still confirm add-ons (virtual terminal, recurring billing, and so on) in PayPal’s documentation.
Hardware is optional for all three: Stripe Terminal, Square readers, and PayPal Zettle/POS devices are separate purchases. The embedded calculators below model processing fees only; add device and subscription costs from each vendor when you compare total spend.
Side-by-side on single charges (Square = online or invoice, matches /compare)
$25.00 charge
Stripe — fee $1.03, net $23.97 (4.12% effective)
Square online or invoice — fee $1.13, net $23.87 (4.52% effective)
PayPal Checkout — fee $1.36, net $23.64 (5.44% effective)
Lowest processing fee on this amount: stripe.
$100.00 charge
Stripe — fee $3.20, net $96.80 (3.20% effective)
Square online or invoice — fee $3.60, net $96.40 (3.60% effective)
PayPal Checkout — fee $3.98, net $96.02 (3.98% effective)
Lowest processing fee on this amount: stripe.
$250.00 charge
Stripe — fee $7.55, net $242.45 (3.02% effective)
Square online or invoice — fee $8.55, net $241.45 (3.42% effective)
PayPal Checkout — fee $9.22, net $240.78 (3.69% effective)
Lowest processing fee on this amount: stripe.
Monthly online volume scenarios
Each scenario assumes every transaction uses the Stripe and PayPal online rates above and Square’s card payments made online or through an invoice line (3.3% + $0.30), not Square Online API (2.9% + $0.30)—no international uplift, currency conversion, or in-person mix. Numbers match monthly processing cost calculator rounding.
$8,000 / month · 160 orders
Solo seller with ~$50 average online order (Square column uses Free-plan card payments made online or through an invoice at 3.3% + $0.30 to match /compare—not the 2.9% + $0.30 Online API row).
Stripe: $280.00 (3.50%)
Square: $312.00 (3.90%)
PayPal: $358.40 (4.48%)
Lowest processing fees this month: stripe ($280.00).
$35,000 / month · 700 orders
Growing e-commerce brand near $50 tickets. PayPal Checkout rates; Square math uses online or invoice card payments, not Online API.
Stripe: $1,225.00 (3.50%)
Square: $1,365.00 (3.90%)
PayPal: $1,568.00 (4.48%)
Lowest processing fees this month: stripe ($1,225.00).
$150,000 / month · 1,500 orders
Higher-volume online store near $100 average ticket. Square at online or invoice rate; custom enterprise quotes not modeled.
Stripe: $4,800.00 (3.20%)
Square: $5,400.00 (3.60%)
PayPal: $5,970.00 (3.98%)
Lowest processing fees this month: stripe ($4,800.00).
Compare processors on one charge
Calculator mode
| Processor | Published rate | Checked | Fee | You keep (net) | Effective fee |
|---|---|---|---|---|---|
| Stripe | 2.9% + $0.30 per successful card charge | October 17, 2026 | $3.20 | $96.80 | 3.20% |
| Square (online) | 3.3% + $0.30 (Square Free, online or invoice card) | October 17, 2026 | $3.60 | $96.40 | 3.60% |
| Square (in-person) | 2.6% + $0.15 (in-person card present, Square Free) | October 17, 2026 | $2.75 | $97.25 | 2.75% |
| PayPal | 3.49% + $0.49 (PayPal Checkout, Guest Checkout, and Venmo) | October 17, 2026 | $3.98 | $96.02 | 3.98% |
| Venmo Business | 1.9% + $0.10 (payments to your Venmo business profile) | October 17, 2026 | $2.00 | $98.00 | 2.00% |
| Cash App Business | 2.6% + $0.15 (payment from customer’s Cash App account to your business account) | October 17, 2026 | $2.75 | $97.25 | 2.75% |
| Clover | 2.6% + $0.10 (Retail Basic hardware on Starter plan — edit if your quote differs) | October 15, 2026 | $2.70 | $97.30 | 2.70% |
| Toast | 2.49% + 15¢ (illustrative example only — not a Toast rate; enter your quoted rate) | Custom pricing (could not check) | $2.64 | $97.36 | 2.64% |
| Helcim (IC+ est.) | Interchange 1.81% + $0.10 + Helcim 0.4% + $0.08 (in-person, $0–$50K monthly card volume) | October 17, 2026 | $2.39 | $97.61 | 2.39% |
Open full processor comparison — same published-rate math as the standalone calculator page.
Stripe fee calculator
2.9% + $0.30 per successful card charge
Results
Live- Processing fee
- $3.20
- You keep (net)
- $96.80
- Effective fee
- 3.20%
Open full Stripe calculator — same published-rate math as the standalone calculator page.
Which processor when
Stripe usually wins on mid-size and large online tickets because the fixed fee is $0.30 versus $0.49 on PayPal Checkout. On Square’s Online API row, the percent matches Stripe (2.9% + $0.30) on every plan; card payments made online or through an invoice on Square Free still use 3.3% + $0.30 unless you upgrade for lower published percentages.
Square fits sellers who want invoicing, a free online store, and in-person tools in one account. Custom API integrations should budget the 2.9% + $0.30 Online API line; sellers taking card payments made online or through an invoice on Free should budget 3.3% + $0.30 (what this page’s calculator embed uses). Upgrade to Plus or Premium when the lower processing and bundled features justify the monthly subscription on Square’s pricing page.
PayPal Checkout can be worth the premium when buyers insist on PayPal wallets, Venmo, or guest checkout flows you already use. On small tickets the $0.49 fixed fee dominates; on larger tickets the 3.49% percent still usually loses to Stripe on processing cost alone—run your actual average order value in the comparison widget.
What this guide does not model
International cards, currency conversion, ACH, instant payouts, chargebacks, and marketplace-specific rates are out of scope. Stripe adds cross-border percentages on its pricing page; PayPal adds cross-market and conversion rules on its business fees table. Use Stripe vs PayPal fees for a longer treatment of those add-ons.