Pay-per-call API platform on Base network via x402 — $0.02/request in USDC.
What it does
lowpaymentfee.com is a pay-per-request API platform that uses the x402 protocol to accept USDC payments on the Base network. The specific endpoint `/api/v1/customers/85` is listed as "Premium API Access" and returns JSON via POST. The x402 challenge confirms the endpoint is live, accepting payments to address `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3` in USDC (contract `0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913`) on Base.
The platform advertises a broad catalog of endpoints spanning data & analytics (metrics, reports, data export, insights), AI & machine learning (sentiment analysis, text summarization, classification, embeddings), finance & Web3 (price feeds, exchange rates, token quotes, gas estimates), and infrastructure utilities (geocoding, validation, conversion, generation). All endpoints are listed at $0.02 per request. The probed endpoint's maxAmountRequired of 20000 base units (USDC has 6 decimals) equals $0.02, consistent with the advertised pricing.
The platform emphasizes simplicity: no API keys, no rate limits, no commitments, and instant access. However, documentation is extremely sparse — the /docs, /api, /pricing, and /README pages all render only a "Connect wallet" prompt with no further technical detail. There is no OpenAPI spec, no request/response schema documentation, and no usage examples available. The purpose and expected input/output of the `/api/v1/customers/85` endpoint specifically is unclear beyond its generic "Premium API Access" label.
Capabilities
Use cases
- —Accessing premium data or services with per-call USDC micropayments on Base
- —Agent-driven API consumption without pre-registration or API keys
- —Programmatic access to a customer resource endpoint with crypto settlement
Fit
Best for
- —Developers wanting zero-signup, pay-as-you-go API access
- —AI agents that can settle x402 payments in USDC on Base
- —Users who prefer crypto micropayments over subscription billing
Not for
- —Users who need detailed API documentation or OpenAPI specs before integrating
- —Applications requiring free or fiat-only payment methods
- —High-volume use cases where per-request pricing may not be economical
Quick start
# The endpoint requires an x402 payment header (USDC on Base).
# 1. Send a POST to get the 402 challenge:
curl -X POST https://lowpaymentfee.com/api/v1/customers/85
# 2. Parse the 402 response, construct an X-PAYMENT header
# with a signed USDC transfer of 20000 base units ($0.02),
# then resend the request with that header.Endpoint
Quality
The x402 challenge is live and pricing is clear ($0.02/request in USDC on Base). However, there is no documentation, no OpenAPI spec, no request/response examples, and the purpose of the /api/v1/customers/85 endpoint is entirely opaque. The docs, pricing, and README pages are all blank beyond a wallet connect prompt.
Warnings
- —No API documentation available — /docs, /api, /pricing, and /README pages all show only 'Connect wallet' with no content.
- —No OpenAPI or schema specification found for any endpoint.
- —The purpose and expected input/output of /api/v1/customers/85 ('Premium API Access') is undocumented and unclear.
- —The broader catalog of endpoints (AI, analytics, finance, utils) listed on the homepage could not be verified or documented beyond their names and prices.
Citations
- —The endpoint returns a 402 x402 challenge with maxAmountRequired of 20000 USDC base units on Base networkhttps://lowpaymentfee.com/api/v1/customers/85
- —All endpoints are priced at $0.02 per request with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —The platform offers endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/customers/85