Pay-per-call premium API access on Base via x402 — $0.02/request in USDC.
What it does
lowpaymentfee.com hosts a collection of pay-per-request API endpoints gated by the x402 protocol. The specific endpoint at `/api/v1/charges/107` is labeled "Premium API Access" and accepts POST requests. Payment is settled on the Base network in USDC (contract 0x8335…2913) with a maximum charge of 20,000 base units, which equals $0.02 per request (USDC uses 6 decimals). No API keys, rate limits, or upfront commitments are required — callers simply attach an X-PAYMENT header with a valid x402 payment proof.
The broader lowpaymentfee.com platform advertises endpoints across four categories: 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 listed endpoints share the same $0.02/request pricing.
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 from the crawled material. The specific functionality behind the `/api/v1/charges/107` "Premium API Access" endpoint is unclear and may be a generic or demonstration endpoint rather than a distinct service.
Capabilities
Use cases
- —Accessing pay-per-request API services without needing API keys or subscriptions
- —Integrating x402-compatible agents with low-cost per-call endpoints on Base
- —Programmatic access to data, AI, finance, or utility endpoints with USDC micropayments
Fit
Best for
- —Developers wanting zero-commitment, pay-as-you-go API access
- —x402-compatible AI agents that need low-cost endpoint calls
- —Projects already operating on the Base L2 network with USDC
Not for
- —Users who need detailed API documentation or guaranteed SLAs
- —Applications requiring high-throughput with predictable flat-rate pricing
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/charges/107 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402_payment_proof>"Endpoint
Quality
The endpoint is live (returns a valid 402 x402 challenge) and pricing is clear ($0.02 USDC on Base). However, there is no OpenAPI spec, no request/response schema, no documentation beyond a wallet-connect prompt, and the specific purpose of /api/v1/charges/107 is undefined. This is effectively a stub listing.
Warnings
- —No OpenAPI or schema documentation available — all /docs, /pricing, /api, /README pages return only 'Connect wallet'
- —The specific functionality of /api/v1/charges/107 ('Premium API Access') is not described anywhere; it may be a generic or demo endpoint
- —No request body schema or response schema is documented, making integration difficult without trial and error
- —The broader platform lists many endpoint categories (AI, finance, data, etc.) but none have documented inputs or outputs
Citations
- —Endpoint returns 402 with x402 challenge accepting USDC on Base network, maxAmountRequired 20000 base unitshttps://lowpaymentfee.com/api/v1/charges/107
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/charges/107
- —Platform advertises $0.02/request pricing with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —Available API categories include Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructurehttps://lowpaymentfee.com
- —Documentation pages (/docs, /api, /pricing, /README) render only 'Connect wallet'https://lowpaymentfee.com/docs