We pay for every API we verify

Agents cannot afford to call an API that does not settle. Before a listing earns its badge here, we send real USDC on Base from our own wallet and confirm that real product comes back.

PayAPI Market is a pay-per-call API marketplace built on the x402 payment protocol, designed for AI agents to discover and pay for APIs autonomously using USDC on Base.

List your API - free · Explore the marketplace

73 Live APIs · 46 independently verified · 454 Endpoints · 100% Kept by providers

x402 verified

We paid for it from our own buyer wallet and received product back. The badge is enforced at database level: it cannot be set without a matching settlement record. 55 listings carry it, of which 9 are our own first-party APIs.

Listed

The provider submitted it and it responds to a challenge. We have not paid for it yet.

Chet Parker is a UK property data specialist based in Portugal. PayAPI Market verifies rather than aggregates, because a marketplace of unverified endpoints is a phone book and an agent needs a credit rating.

UK property data API, Companies House API, postcode lookup API, pay per request API, x402 marketplace, AI agent API marketplace, MCP API directory, USDC API payments, micropayment API

Why PayAPI vs enterprise data providers

Enterprise data providers charge $15,000 per year with annual contracts. PayAPI Market charges $0.002 per request with no commitment. That is 7,500,000 requests before you break even on the enterprise plan. AI agents cannot fill out forms, enter credit cards, or sign contracts. They need x402.

USDC on Base: sub-second settlement, less than $0.001 transaction fee. Zero support tickets needed.

How it works

1. List your API: Add your endpoint URL, set a price per request (from $0.001), write a description. Free, takes 5 minutes.
2. AI agents discover you: Your API appears in the Model Context Protocol registry. Claude Desktop, Cursor, LangChain agents, and any MCP-compatible client find you automatically.
3. Agents pay, you keep 100%: Every request triggers an x402 micropayment. USDC settles on Base in under a second. No invoicing, no chasing, no support needed.

Who is this for

You do not need to be a developer. You need domain expertise. Mortgage brokers, recruiters, accountants, estate agents, solicitors, logistics managers, compliance officers, insurance underwriters, pharmacists, and quantity surveyors can all monetise their specialist knowledge through APIs on PayAPI Market.

Live API listings

73 live APIs, 454 endpoints total across property, companies, weather, vehicles, finance, HMO licensing, waste collection, air quality, text analytics, data intelligence, and more.

Browse all APIs — view the full marketplace →

Pricing

Free to list. No per-request fee, you keep 100% of every settlement. Featured is a flat $49/month for placement only. No subscriptions for buyers. Agents pay per request.

• List your API - free
• Explore the marketplace
• Estimate your revenue
• See pricing

The agent economy is here. Your knowledge should be earning.

73 live APIs with zero hours of customer support. Yours could be next. List your API - free.

Full catalogue

A selection of the 73 live APIs on PayAPI Market. See all in the marketplace →

• UK Data API: 24 endpoints. UK government and public data: Land Registry, EPC, Companies House, DVLA, BoE rates, weather, crime, flood risk. $0.001–0.002 per request.
• Email Verification API: 4 endpoints. SMTP check, disposable-domain filter, catch-all detection, role-account heuristics. $0.001 per request.
• Company Enrichment API: 6 endpoints. Companies House lookup plus directors, filings, SIC codes, financials. $0.003–0.005 per request.
• Postcode & Address Lookup: 5 endpoints. UK postcode to address, validation, autocomplete, geocoding. $0.001 per request.
• Currency & Crypto API: 5 endpoints. FX rates, crypto spot prices, historical series, conversion. $0.001 per request.
• Screenshot & PDF Capture: 4 endpoints. Headless browser page rendering, full-page screenshots, PDF export. $0.002 per request.
• DNS & Domain Intelligence: 5 endpoints. WHOIS, DNS A/AAAA/MX/TXT, SPF/DKIM, nameserver history. $0.002 per request.
• Web Scraper & Content Extractor: 4 endpoints. HTML to structured data, readability extraction, metadata. $0.002 per request.
• IP Geolocation API: 4 endpoints. IP to country, city, ASN, ISP, timezone. $0.001 per request.
• QR Code API: 4 endpoints. QR generation, decoding, styling, batch. $0.001 per request.
• UK HMO Licence API: 3 endpoints. HMO licence check by address or postcode, full licence details. 124,715 licensed rental records across 65 UK councils, as of May 2026. $0.020–0.040 per request.
• TensorFeed: 60 endpoints. Real-time AI ecosystem data: AI news, model pricing, live service status, MCP registry, AI papers, GPU pricing. $0.020–0.060 per request.
• Official US Business Registry Evidence API: 1 endpoints. Official-source US Secretary of State business-registry evidence for KYB, merchant underwriting, and compliance review across 17 active states. $0.010 per request.
• x402 Agent-Payment Infrastructure: 12 endpoints. x402/MCP layer for paid AI/data calls, crypto conversion quotes, progress streams, receipts, and agent spend governance. $0.001–5.000 per request.
• Merchant Risk WHOIS Domain Evidence API: 1 endpoints. WHOIS and domain-age evidence for merchant underwriting, vendor due diligence, and website legitimacy checks. $0.010 per request.
• IRS 990 Nonprofit Charity Grant Evidence API: 1 endpoints. IRS 990 nonprofit search for charity verification, donor research, grant prospecting, and foundation diligence. $0.010 per request.
• Building Permits Roof Age Solar AHJ Evidence API: 1 endpoints. Official-source building-permit search for contractor leads plus roof-age, property-insurance permit history, solar/AHJ coverage QA, P&C underwriting, COPE permit evidence, and permit source-drift checks. Parameters: city, query/keyword, maxResults. Safe default if city/query are omitted: Austin roof permits with an explicit warning. Deterministic test: city=austin&query=roof&maxResults=5 returns recent permit-event records; city=austin&query=solar&maxResults=5 demonstrates solar/AHJ project evidence.. $0.010 per request.
• SEC EDGAR Filings Public Company Evidence API: 1 endpoints. SEC EDGAR company and filing lookup for investor due diligence, financial research, and 10-K/10-Q discovery. $0.010 per request.
• M2M Trust Lean Six Sigma API: 6 endpoints. Deterministic Lean Six Sigma tools: SPC audit, process capability, Pareto analysis, descriptive stats, and data quality audit. $0.001 per request.
• UK Air Quality API: 1 endpoints. Current UK air quality from DEFRA UK-AIR by postcode, with pollutant readings from nearest monitoring stations. $0.001 per request.
• Text Metrics API: 5 endpoints. Deterministic text analysis for agents: word counts, readability scores, word frequency, style warnings, and aggregate reports. $0.001 per request.
• UK Waste Collection API: 5 endpoints. UK council waste collection schedules by postcode, address, or UPRN across participating councils. $0.001 per request.
• IRONCLAW BTC Node: 24 endpoints. Bitcoin blockchain data from a real full node: fees, mempool, transactions, address portfolio, tx tracing, whale alerts, SEC insider trades, web scraping, AI summarization.. $0.001–0.010 per request.
• Anchor-x402: 16 endpoints. Multi-chain x402 services: OFAC sanctions screening, dual-chain hash anchoring, signed RNG, due-diligence investigator, and LLM utilities. Settles on Base USDC, Solana USDC, or Polygon JPYC. $0.001–$1.77 per request.. $0.001–1.770 per request.
• StockWaves: 14 endpoints. China & global market data for AI agents — real-time Chinese internet pulse (Weibo/Baidu/Douyin), structured China market news & events, industrial-theme momentum, quant signals across A-share/HK/US equities, BTC directional signal, crypto microstructure, and tactical ETF allocation. Plus stateless portfolio optimizer. x402 USDC on Base or Solana, no API key.. $0.030–0.500 per request.
• OSS2API Multi-skill Agent API: 4 endpoints. Open-source AI and web-automation tools as x402-paid agent endpoints: image background removal, URL content analysis, Playwright browser extraction & screenshots, and multi-phase web security scan.. $0.010 per request.
• NewsMesh: 1 endpoints. Real-time news API for AI agents: search and filter articles from thousands of global sources. $0.010 per request.
• AgentBodega Agent Tools: 52 endpoints. x402-paid agent utility APIs for public data, social lookup, status checks, cloud health, domain readiness, x402 inspection, artifacts, and launch-readiness audits. $0.001–0.060 per request.