How long do x402 payments take to finalize?
9/9/2026, 6:37:57 PM · llm:mimo:mimo-v2.5
The dispatch, itemised.
Breaking down: "How long do x402 payments take to finalize?"
Identified 1 research target(s) to investigate; these are not established facts
Deep mode: up to 4 paid/cached reads plus one bounded gap-expansion pass when needed.
Discovered 21 verified source(s)
Recalled 60 past runs on this subject — how these sources performed when they were available.
ERC-8004 reputation loaded — composite scores on this subject.
Claim-aware portfolio selected 2/4 positive proposal(s): 2 cached + 0 fresh, predicting 1/1 claim(s) above the evidence floor with $0.000000/$0.020000 fetch USDC reserved.
Free-preview pre-check maps an actionable source to every sub-claim (1/1); paid reading may proceed within the budget.
Preview directly matches the question about x402 settlement latency, offering lab-measured benchmarks. This source has strong past performance (57% citation rate) and is already cached, so reuse at zero cost. It directly supports target 0. — selected for the claim-aware evidence portfolio (targets claim 1; 0 fetch USDC, 1 attention slot).
Article title exactly matches the user question. The preview promises an overview of x402 settlement timing. As a cached source, it's free and directly relevant. It supports target 0. It's a strong complement to the Arc benchmarks with cross-protocol context. — selected for the claim-aware evidence portfolio (targets claim 1; 0 fetch USDC, 1 attention slot).
Preview discusses Web3 identity, not settlement timing. Off-topic for this specific question about payment finalization latency. Not worth the toll.
Preview discusses Stripe Projects and agent integrations, but not x402 payment finalization timing. While Stripe has high reputation, this specific article's preview lacks direct relevance to settlement latency for target 0.
First-party Keryx source on buyer recovery, but the preview doesn't mention settlement timing. However, it's first-party (100% citation rate) and cached. Might contain implicit details on payment flow, but low direct relevance. Still, it's free and could have useful context. — the claim-aware portfolio chose a stronger, less redundant set inside the 4-source attention and $0.020000 fetch-budget caps, so this proposal stays unspent.
Preview covers crypto payment adoption in euro merchants, not x402 settlement speed. General crypto news, not technical timing data.
Preview discusses stablecoins and settlement cycles in market context, but not specific x402 finalization times. Indirectly related, but not precise enough for the question.
Preview mentions USDC settles in seconds, which is relevant to payment finality. While not x402-specific, it provides context on stablecoin settlement speed, which x402 uses. Cached and cheap. Supports target 0 with general settlement timing info. — the claim-aware portfolio chose a stronger, less redundant set inside the 4-source attention and $0.020000 fetch-budget caps, so this proposal stays unspent.
Preview describes x402 as a payment rail for agents, but doesn't mention settlement timing. Relevant topic, but missing the specific latency detail needed. Cached, but not directly answering the question.
Preview discusses nanopayments and batching, not finalization time. Micropayments are tangential, but not directly about speed.
Preview covers idempotency keys for double-spends, a reliability topic, not settlement latency. Different concern than finalization speed.
Gardening article; completely off-topic. No relevance to x402 payments.
Retro gaming hardware article; off-topic. No relevance to payment systems.
Preview discusses AI agents and ontologies, not payment settlement. Topical area but missing the core question about timing.
Metadata only preview about AI model adoption; not relevant to payment finalization. No content on settlement timing.
Preview about AI tutors; off-topic. No connection to x402 payments.
Preview on low-risk DeFi for Ethereum; general Ethereum strategy, not x402 settlement latency. Not specific enough.
Mystic/occult article; completely off-topic. No relevance.
Music news about bands; off-topic. No relevance to payments.
Agent spend wallet ready: 0x29028Fe1122E17Fe7863A22701e863FE4DaE1aFB (balance sufficient)
Reused cached Arc Settlement Benchmarks — Measuring x402 settlement latency on Arc (free) — S1
Reused cached Web Payments Review — How long do x402 payments take to finalize? (free) — S2
Sub-claim "How long do x402 payments take to finalize in the context of…": 0% covered — The gathered sources provide conflicting data on x402 payment finality (180ms vs. 15 seconds) but neither mentions Keryx. S1 and S2 discuss general x402 settlement times on Arc testnet and Ethereum L1 respectively, but there is no information about Keryx's specific system or its use of x402. The sub-claim specifically asks about Keryx's context, which is not addressed.
The current coverage is 0.0 because none of the gathered sources mention Keryx. The skipped source 'Keryx Engineering (first-party) — Recovering a Keryx paid research job' is directly relevant and could provide information about Keryx's payment finality in its system. Its price (0.002) is within the remaining budget (0.02), making it an affordable and targeted purchase to fill the gap. Other skipped sources are unrelated to Keryx.
Filling gap — buying Keryx Engineering (first-party) — Recovering a Keryx paid research job ($0.002)…
Paid $0.002 to Keryx Engineering (first-party) — Recovering a Keryx paid research job (settled 6a22c254-9…) — S3
Final check — "How long do x402 payments take to finalize in the context of…": 0% assessed
Final coverage assessment — The research question asks specifically about x402 payment finalization time in the context of Keryx's system. Source S1 provides a direct answer (180ms median, 240ms p95 on Arc testnet with BFT consensus), but this is about Arc's testnet, not explicitly about Keryx's system. Source S2 gives a different timing (about 15 seconds) but again refers to a general view of x402 payments, not Keryx-specific. Source S3 is from Keryx Engineering but does not contain any information about payment finalization times; it's about buyer recovery. Therefore, no source explicitly answers how long x402 payments take to finalize in Keryx's system specifically.
Synthesizing a grounded answer from 3 source(s)…
Relevance review returned; only checked excerpts can retain support, and review cannot raise it.
⚖️ Sources disagreed on X402 payment finalization time — S1 roughly 180 milliseconds on Arc testnet vs S2 about 15 seconds when each payment is its own transaction → trusted S1 (S1 provides specific, measured latency data for a particular implementation (Arc testnet) using batched settlements, while S2 provides a general estimate for a different implementation pattern (individual transactions on Ethereum L1). The specific data from S1 is more reliable for its stated context.)
Verified — S1 supports claim 1 at 80%: “Across thousands of submitBatch calls on Arc testnet, x402 batched settlements finalize in roughly 180 milliseconds (measured median 178ms, …”
Verified — S1 supports claim 1 at 70%: “Arc's BFT consensus delivers sub-second finality, so a Gateway-batched payment confirms in well under a quarter second — it is not block-tim…”
Below reward gate — S2 supports claim 1 at 30%: “In our reading, an x402 payment takes about 15 seconds to settle, similar to an Ethereum L1 block time, because each payment is its own tran…”
Rejected 0 invalid evidence span(s) and 2 unsupported citation marker(s); rejected markers cannot receive citation rewards.
Drafted answer citing 1 source(s)
Confidence: Low — 1 sub-claim remain below the evidence threshold, 1 disagreement adjudicated.
Arc Settlement Benchmarks contributed 100% → reward $0.02
Settled $0.02 citation reward → Arc Settlement Benchmarks (379618b9-a…)
Done. Spent $0.022 across 2 confirmed/simulated payment(s) to creators.
> ⚠ Low confidence — 1 sub-claim remain below the evidence threshold, 1 disagreement adjudicated within budget. Treat this as provisional.
X402 payment finalization times vary depending on the implementation context. On the Arc testnet, x402 batched settlements finalize in roughly 180 milliseconds, with a measured median of 178ms and a p95 of 240ms, because Arc's BFT consensus delivers sub-second finality . However, another review indicates that an x402 payment takes about 15 seconds to settle, similar to an Ethereum L1 block time, when each payment is its own transaction waiting to be mined. The provided Keryx Engineering document does not contain information on x402 payment finalization times.
Evidence ledger — quotes verified before rewards
How long do x402 payments take to finalize in the context of Keryx's system?
0%“Across thousands of submitBatch calls on Arc testnet, x402 batched settlements finalize in roughly 180 milliseconds (measured median 178ms, p95 240ms).” [S1] Measuring x402 settlement latency on Arc
“Arc's BFT consensus delivers sub-second finality, so a Gateway-batched payment confirms in well under a quarter second — it is not block-time-bound the way an Ethereum L1 transaction is.” [S1] Measuring x402 settlement latency on Arc
Footnotes — each one pays its author
- 1Measuring x402 settlement latency on ArcArc Settlement Benchmarks100%+$0.02
Portable research receipt
Take the evidence trail with you
One deterministic JSON bundle binds the answer, visible decisions, exact article versions, claim evidence and a Circle-settlement snapshot under SHA-256. Retain the digest to detect later changes; the self-check is not a publisher or Keryx signature.
Exact receipt still current
1 exact cited article version still match Keryx's current index.
Carries this dispatch’s question as context — never its answer. The next dispatch is read from sources bought for it.