x402 vs Agentic Commerce Protocol (ACP)
The map lists them as complementary: sites and agents commonly implement both.
| x402 | Agentic Commerce Protocol ACP | |
|---|---|---|
| Lifecycle step | 7 Pay: Settle the bill | 7 Pay: Settle the bill |
| Answers | How can an HTTP client pay per-request or per-resource, in stablecoins, without accounts, API keys, or signup? | How do a buyer's agent and a merchant complete a deterministic, programmatic checkout without the agent becoming the merchant of record? |
| Governed by | x402 Foundation, a Series of LF Projects, LLC (Linux Foundation); operational launch announced 2026-07-14; Executive Director Michael Hursta from 2026-10-01; 50+ members | Technical Steering Committee (up to 7 org seats); OpenAI, Stripe, and Meta are lead maintainers, with OpenAI and Stripe as Founding Maintainers holding last-resort veto over mission, neutrality, security, and fork-integrity decisions |
| Status (issuer's words) | Open, neutral standard for internet-native payments | Beta open standard, interaction model for connecting buyers, agents, and businesses |
| Version | x402 protocol specification v2, transports-v2/http.md | 2026-04-17 (date-versioned spec; unreleased/ tracks current development) (2026-04-17) |
| Form / transport | HTTP header | endpoint |
| Found at | none — signalled per-request via the 402 status code, not a fixed well-known path | Bilateral capability negotiation (per RFC: capability_negotiation) between agent platform and merchant; no fixed well-known path published |
| Implementation | multi-implementation — x402 Foundation (x402.org live dashboard) | multi-implementation — OpenAI and Stripe (project README) |
| Evidence | 5 verified | 3 verified, 2 reported |
| Primary use case | Accept payments from agents | Let agents buy on behalf of a person |
| Last verified | 2026-10-23 (current) | 2026-10-23 (current) |
| Specification | https://github.com/x402-foundation/x402/blob/main/specs/transports-v2/http.md | https://github.com/agentic-commerce-protocol/agentic-commerce-protocol |
When to use which
- Choose x402 when your question is “How can an HTTP client pay per-request or per-resource, in stablecoins, without accounts, API keys, or signup?” and you accept its maturity: status "Open, neutral standard for internet-native payments", implementation multi-implementation (x402 Foundation (x402.org live dashboard)).
- Choose Agentic Commerce Protocol when your question is “How do a buyer's agent and a merchant complete a deterministic, programmatic checkout without the agent becoming the merchant of record?” and you accept its maturity: status "Beta open standard, interaction model for connecting buyers, agents, and businesses", implementation multi-implementation (OpenAI and Stripe (project README)).
Read the full articles
- x402: How can an HTTP client pay per-request or per-resource, in stablecoins, without accounts, API keys, or signup?
- Agentic Commerce Protocol: How do a buyer's agent and a merchant complete a deterministic, programmatic checkout without the agent becoming the merchant of record?