Adyen vs Square Payments

Adyen and Square Payments are both Online Card Payment APIs, compared here on pricing, compliance, capabilities, and developer experience from structured, cited data - not reviews or paid placement. For coding-agent use, Adyen scores higher on agent-friendliness (75 vs 65).

Comparedby a transparent data-readiness score computed from each API's published, sourced fields. No reviews, no paid placement. How we rank.

Data last verified 2026-06-21, with every field cited on each profile.

Head-to-head, from published, cited fields (auto-generated; no paid placement)
Field	Adyen	Square Payments
Starting price	$0.13 transaction	$0.30 transaction + percent
Pricing model	Sales-led	Hybrid
Free tier	✗	✗
Self-serve signup	✓	✓
SOC 2	Type II	Type II
HIPAA	·	·
GDPR	✓	✓
Webhooks	✓	✓
Sandbox	✓	✓
Documented actions	31	26

Full data and citations: Adyen · Square Payments. See more Online Card Payment APIs.