ACP vs AP2
Last verified 2026-05-31Short answer: ACP and AP2 differ in scope. ACP, the Agentic Commerce Protocol (OpenAI and Stripe, 29 September 2025), is a checkout protocol that completes a purchase and powers Instant Checkout in ChatGPT. AP2, the Agent Payments Protocol (Google, 16 September 2025), is a broader, payment-agnostic framework for authorizing agent-led payments across networks, and extends the A2A protocol and MCP. Different authors, different focus; a merchant can adopt both.
Filter standards:
| Criterion | ACP | AP2 |
|---|---|---|
| Author / steward | OpenAI and Stripe | Google (60+ orgs) |
| Announced | 29 Sep 2025 | 16 Sep 2025 |
| Open-source status | Open source, Apache 2.0 | Open specification (public GitHub) |
| What it is | Agent checkout / commerce protocol | Agent payments framework |
| Payment type | Card and existing processors (Stripe SPT) | Payment-agnostic (cards, stablecoins, bank transfers) |
| Transport | HTTP (OpenAPI); MCP since 2026-04-17 | Extension of A2A and MCP |
| Primary use | Buy products inside ChatGPT (Instant Checkout) | Authorize agent-led payments across platforms |
| Notable adoption | OpenAI, Stripe, Etsy, Shopify (coming) | Mastercard, PayPal, Amex, Adyen, Coinbase |
Table last verified .
Frequently asked questions
Is the Agentic Commerce Protocol the same as AP2?
No. ACP (OpenAI + Stripe) focuses on agent checkout; AP2 (Google) is a broader payment-agnostic framework.
Which was announced first, ACP or AP2?
AP2 was announced on 16 September 2025, ACP on 29 September 2025.
Can a merchant support both ACP and AP2?
Yes. They address different layers of the stack and can coexist.