The best x402 APIs for AI agents (2027 list)
Updated 26 October 2026
The best x402 APIs are the ones an AI agent can pay per call in USDC and be sure of getting a real result. Below are 30 of them across data, finance, intelligence, tools and verification, each picked from PayAPI Market's own catalogue because we paid one of its routes ourselves and got a genuine response with an on-chain receipt.
Every API here works without an API key or account: your agent receives an HTTP 402 with the price, pays in USDC on Base, Solana or Algorand, and gets the response. Prices start at a tenth of a US cent per call. Connect your agent over MCP.
How this list is chosen
This list is curated from PayAPI Market's verified catalogue by fixed rules, not by payment or sponsorship. An API is eligible only if all of these are true:
- It is live and settlement-verified: PayAPI paid one of its routes from its own wallet, received real product back and holds an on-chain USDC receipt.
- It comes from an independent provider who listed it. Coinbase Bazaar imports that we verified but whose providers have not signed up ("Unclaimed (bazaar)"), and PayAPI's own first-party APIs, are excluded.
- Its latest health check is healthy, and its live 402 pays the wallet the provider registered.
- Its lowest price per call is between $0.001 and $1 USDC.
- It has a real description (80 characters or more) and a unique listing page.
- It is not a novelty or entertainment-only API.
On 26 Oct 2026, 294 APIs met these rules. Within each category they are ranked by PayAPI's reliability score (listings not yet scored come after scored ones), then by the number of settlement-verified routes, then by how long they have been listed. To keep the list varied, each provider appears at most once per category and twice on the page. We show the top six per category.
Prices are the listing's range as advertised in its live 402. Chains are the networks each API advertises. PayAPI's settlement receipts for these 30 are on Base. Reliability scores were last computed on 6 Sep 2026, so many newer listings are unscored; that is why scored listings lead.
Regenerated weekly from the same rules, with the updated date shown under the heading. An API drops off automatically if it stops being healthy, its 402 stops paying the registered wallet, or its verification is withdrawn.
Full method and figures: The x402 API market: a snapshot from PayAPI Market, October 2026 (Zenodo, DOI 10.5281/zenodo.23658608)
Data
Public-record, economic and market data that an agent can buy one call at a time.
| API | What it does | Price per call (USDC) | Chains | Listing |
|---|---|---|---|---|
| LaborPulse On-chain receipt |
US labour-market signal in one call, combining jobs, unemployment, wage growth and JOLTS data from the BLS. | 0.05 | Base, Solana | payapi.market/api/laborpulse |
| ProviderSignal Dental Market Intelligence On-chain receipt |
US dental provider intelligence: state board licensure, DSO affiliation, discipline and Medicaid participation, with citations. | 0.5 to 2.5 | Base | payapi.market/api/providersignal-dental-market-intelligence |
| Parallax On-chain receipt |
Seller-side x402 market data computed from public on-chain settlements, with per-seller stats and buyer baskets. | 0.01 to 0.05 | Base, Solana | payapi.market/api/parallax |
| CSV Drift Evidence On-chain receipt |
Compares a baseline and a candidate CSV and reports column, type and missing-value drift as JSON evidence. | 0.015 | Base | payapi.market/api/csv-drift-evidence |
| HALOWERK EV Charging On-chain receipt |
EV charging points near a coordinate from OpenStreetMap, with operator, connectors, power and access details. | 0.005 | Base | payapi.market/api/halowerk-ev-charging |
| CanonicalHash, JSON Canonicalization API On-chain receipt |
RFC 8785 JSON canonicalisation with SHA-256 or SHA-512 hashing and signed attestations. | 0.001 to 0.01 | Base, Solana | payapi.market/api/canonicalhash-json-canonicalization-api |
Finance
Market signals, filings comparison and underwriting maths for agents that make or check financial decisions.
| API | What it does | Price per call (USDC) | Chains | Listing |
|---|---|---|---|---|
| SameDayDesk Machine Commerce APIs On-chain receipt |
Eleven paid routes covering Morpho risk, company and wallet enrichment, repository scanning and structured extraction. | 0.002 to 0.25 | Base | payapi.market/api/samedaydesk-machine-commerce-apis |
| Crypto Snapshot Pro - AI Trading Signals On-chain receipt |
Crypto trading signals with entry, target, stop, risk to reward and a conviction score per request. | 0.025 | Base | payapi.market/api/crypto-snapshot-pro-ai-trading-signals |
| MacroPulse On-chain receipt |
US macro conditions (growth, inflation and policy) distilled into one read an agent can gate decisions on. | 0.05 | Base, Solana | payapi.market/api/macropulse |
| Cognilode Ticket Resale Underwriter On-chain receipt |
Ticket resale underwriting: break-even, safe buy ceiling, ROI, downside and a buy or no-buy decision. | 0.005 | Base | payapi.market/api/cognilode-ticket-resale-underwriter |
| ATLAS SEC Filing Delta On-chain receipt |
Compares US-GAAP facts between SEC filings, with source links and absolute and percentage changes. | 0.01 to 0.03 | Base | payapi.market/api/atlas-sec-filing-delta |
| Crypto Technicals & Web Utilities On-chain receipt |
BTC/USDT last price, high, low and volume, with further paths described in its 402 response. | 0.001 | Base, Solana | payapi.market/api/crypto-technicals-web-utilities |
Intelligence
Threat intelligence, DNS and x402 market intelligence for research and monitoring agents.
| API | What it does | Price per call (USDC) | Chains | Listing |
|---|---|---|---|---|
| zFinia machine_economy_changes_since On-chain receipt |
Material x402, machine-payment and agent-commerce changes since an agent last checked, with a resumable cursor. | 0.01 | Base | payapi.market/api/zfinia-machine-economy-changes-since |
| ot-intel-api On-chain receipt |
OT and ICS indicator-of-compromise enrichment, returning threat pulse counts and ASN data. | 0.01 | Base | payapi.market/api/ot-intel-api |
| TELESINT On-chain receipt |
Turns Telegram threat chatter into structured threat intelligence: IOCs, actors and OSINT signals. | 0.01 to 0.05 | Base | payapi.market/api/telesint |
| AgentPay On-chain receipt |
A set of 28 x402 routes; the settlement-verified route returns Ethereum gas prices. | 0.003 to 0.1 | Base | payapi.market/api/agentpay |
| DNS Inspector record lookup On-chain receipt |
DNS records for a URL (A, AAAA, MX, TXT, CAA and more) plus SPF and DMARC posture. | 0.02 | Base | payapi.market/api/dns-inspector-record-lookup |
| MCR Verified Demand Gap On-chain receipt |
Searches live x402 discovery registries and ranks service candidates by relevance, demand and price. | 0.01 | Base | payapi.market/api/mcr-verified-demand-gap |
Tools
Conversion, media generation and general utility endpoints that save an agent writing its own code.
| API | What it does | Price per call (USDC) | Chains | Listing |
|---|---|---|---|---|
| Lemon Toolshed On-chain receipt |
19 conversion tools for agents across Markdown, HTML, JSON, YAML, CSV and plain text. | 0.002 to 0.006 | Base, Solana | payapi.market/api/lemon-toolshed |
| kino402 On-chain receipt |
Video generation and text-to-speech for agents, priced per input through a parametric quote. | 0.007 to 16.701 | Base, Solana | payapi.market/api/kino402 |
| Bounty Engineer Agent Commerce API On-chain receipt |
Exchange funding rates, web-to-Markdown extraction, SEO audits and JSON validation in one API. | 0.001 to 0.01 | Base, Solana | payapi.market/api/bounty-engineer-agent-commerce-api |
| x402 MCP Tools On-chain receipt |
Four MCP tools: QR code generation, image processing, LLM text analysis and URL fetch. | 0.01 to 0.02 | Base | payapi.market/api/x402-mcp-tools |
| zFinia Accessibility Contrast Calculator On-chain receipt |
WCAG 2.x contrast ratio for one foreground and background colour pair. | 0.001 | Base | payapi.market/api/zfinia-accessibility-contrast-calculator |
| Flat-rate LLM and EVM toolkit On-chain receipt |
48 endpoints at one flat price: EVM chain reads, ERC-20 safety checks, URL to Markdown, DNS checks and LLM completions. | 0.005 | Base | payapi.market/api/flat-rate-llm-and-evm-toolkit |
Verification
Checks an agent runs before it signs, pays, publishes or trusts something.
| API | What it does | Price per call (USDC) | Chains | Listing |
|---|---|---|---|---|
| MachineMint, Unsigned Base Transaction Preflight On-chain receipt |
Simulates an unsigned Base transaction before signing and returns PASS, REVIEW or FAIL with flagged risks. | 0.01 | Base | payapi.market/api/machinemint-unsigned-base-transaction-preflight |
| NexusEval Marketing Preflight On-chain receipt |
Pre-publication QA for marketing copy, returning structured quality and risk flags. | 0.01 | Base | payapi.market/api/nexuseval-marketing-preflight |
| 10x402 On-chain receipt |
Lints a seller's live x402 402 response against 82 source-cited conformance checks and grades it. | 0.004 to 0.12 | Base, Solana | payapi.market/api/10x402 |
| Contract Powers On-chain receipt |
Lists the admin powers a smart contract retains (upgrade, mint, pause, blacklist) with on-chain evidence. | 0.05 | Base | payapi.market/api/contract-powers |
| Novarithm Trust & Commerce Checks On-chain receipt |
Agent trust and commerce checks, including MCP, A2A and x402 probes and seller risk. | 0.001 to 0.25 | Base | payapi.market/api/novarithm-trust-commerce-checks |
| SendCheck On-chain receipt |
Pre-send check for an EVM address: checksum, wallet or contract, and activity on the chosen chain. | 0.01 to 0.05 | Base | payapi.market/api/sendcheck |
Find more
Frequently asked questions
What are the best x402 APIs?
The best x402 APIs are ones you can trust to deliver what you paid for. This list only includes APIs that PayAPI Market has paid itself and received real output from, with an on-chain USDC receipt anyone can check, and it then ranks them by reliability within each category.
What does settlement-verified mean?
PayAPI Market paid one route of the API from its own wallet, received a real product response and recorded the on-chain USDC receipt. Verification covers that paid route, not every route on the listing.
Do I need an API key or an account to use these APIs?
No. Each API answers an unpaid request with HTTP 402 and its price. Your agent signs a USDC payment, retries the request and gets the response. There are no buyer keys or accounts.
Which chains can my agent pay on?
These APIs accept USDC on Base, Solana or Algorand, depending on the listing. Every API on this page accepts Base, and the chains column shows the others each one advertises in its live 402 response.
How can I get my API on this list?
List it free on PayAPI Market at payapi.market/providers. Once a test payment settles and the API meets the criteria on this page, it becomes eligible at the next refresh. Providers keep 100% of what agents pay.