Head to head
Adyen vs Square
As a payments API, Square rates higher on the APIbenchmarks Index, 85.9 to 76.1, a 9.8-point gap. Here is how they compare on each criterion.
Criterion by criterion
| Criterion | Adyen | Square |
|---|---|---|
| Documentation & DX | ||
| Reliability | ||
| Ecosystem & SDKs | ||
| Accessibility | ||
| APIbenchmarks Index | 76.1 | 85.9 |
Specifications
| Adyen | Square | |
|---|---|---|
| Best for | Enterprise unified commerce acquirer | Omnichannel (online + in-person) payments |
| Free tier | No | Free APIs/SDKs + sandbox; sellers pay per transaction |
| Pricing | Interchange++ (€0.11 + IC + ~0.6%) | Per transaction (2.6% + $0.15 in-person) |
| Official SDKs | 12 languages | 12 languages |
Is Adyen better than Square?
On the APIbenchmarks Index, Square rates higher (85.9 vs 76.1). It leads on the four weighted criteria, but price is reported separately, so the best choice still depends on your budget.
Verdict in one line
Square leads by 9.8 points (85.9 vs 76.1) and wins 3 of 4 criteria; Adyen wins 1.
Winner by criterion
| Criterion | Winner | ||
|---|---|---|---|
| Documentation & DX | 84 | 86 | |
| Reliability | 95 | 86 | |
| Ecosystem & SDKs | 78 | 84 | |
| Accessibility | 38 | 88 |
Choose Adyen if… / choose Square if…
- →reliability matters most to you (95 vs 86)
- →your use case matches its focus: enterprise unified commerce acquirer
- →documentation & dx matters most to you (86 vs 84)
- →ecosystem & sdks matters most to you (84 vs 78)
- →accessibility matters most to you (88 vs 38)
- →you want a free tier to start (Free APIs/SDKs + sandbox; sellers pay per transaction)
- →your use case matches its focus: omnichannel (online + in-person) payments
Pricing side by side
- Model
- Interchange++ (€0.11 + IC + ~0.6%)
- Free tier
- No
- Interchange++ (standard)Interchange + scheme fees + ~0.60% acquirer markup
- Per-transaction processing fee~€0.10–€0.15 per transaction
- No recurring platform fees$0 setup / monthly / integration / closure
- Model
- Per transaction (2.6% + $0.15 in-person)
- Free tier
- Free APIs/SDKs + sandbox; sellers pay per transaction
- Square Free$0/mo
- Square Plus$49/mo
- Square Premium$149/mo
- Online API2.9% + 30¢
- ACH via API1%, $1 min, $5 cap
- Custom / EnterpriseCustom
Vendor-published pricing, verified 2026-06-27 (Adyen) and 2026-06-27 (Square).
SDK and language coverage
Both · 7
JavaPHPNode.js.NET (C#)PythonGoRuby
Only Adyen · 5
Adyen Web (JavaScript) Drop-in/ComponentsiOS (Swift/Objective-C)AndroidReact NativeTerminal API libraries (C#, Go, Java, Node, PHP, Ruby)
Only Square · 5
Web Payments SDK (JavaScript)In-App Payments SDK (iOS)In-App Payments SDK (Android)React Native pluginMobile Payments / Terminal SDK
Strengths and weaknesses
- +Single unified API and integration across online, in-app, and in-store (POS) with consistent shopper recognition
- +Interchange++ transparent pricing rather than blended rates, clear visibility into interchange, scheme fees, and markup
- +Strong developer experience: OpenAPI specs, interactive API Explorer, generated SDKs, sandbox with test cards, short release cycles
- –Pricing and minimum monthly invoice make it expensive/opaque for small and low-volume merchants
- –Aggressive automated risk/fraud blocks with no clear appeal process, and reports of frozen or held funds
- –Email-only support with no phone line; slow IT/support responsiveness is a recurring complaint
- +Single API and account unifies online, in-app, and in-person (omnichannel) payments
- +Transparent flat-rate pricing with no monthly fee, PCI fee, or minimums on the free tier
- +Broad payment-method support: cards, Apple/Google/Cash App Pay, ACH, Afterpay, gift cards
- –Risk-driven account freezes and fund holds with little notice are a recurring, serious complaint
- –Phone support limited to first 90 days; slow, hard-to-escalate help for complex issues
- –Flat-rate pricing becomes expensive at high volume versus interchange-plus processors
Adyen vs Square: questions
- Which has better documentation, Adyen or Square?
- Square scores higher on documentation and developer experience: 86 vs 84 out of 100.
- Which is more reliable, Adyen or Square?
- Adyen scores higher on reliability: 95 vs 86 out of 100.
- Do Adyen and Square have a free tier?
- Adyen: no free tier. Square: yes (Free APIs/SDKs + sandbox; sellers pay per transaction).
- How are Adyen and Square priced?
- Adyen: Interchange++ (€0.11 + IC + ~0.6%). Square: Per transaction (2.6% + $0.15 in-person).
- Which has more official SDKs?
- Both list 12 official SDKs.