x402-gated API platform on Base offering data, AI, finance, and utility endpoints at $0.02/request via USDC.
What it does
lowpaymentfee.com is an x402 payment-gated API platform that hosts a collection of endpoints spanning data analytics, AI/ML inference, finance/Web3 data, and general utility services. All endpoints are pay-per-request with no API keys, no rate limits, and no sign-up required — callers simply attach an x402 payment header to each request.
The specific endpoint at `/api/v1/stripe/charges/179` is listed as "Premium API Access." Its x402 challenge advertises a maximum cost of 20,000 base units of USDC (asset 0x8335…2913) on the Base network, which equals $0.02 per request (USDC uses 6 decimals, so 20000 / 10^6 = $0.02). Payment is made to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 using the "exact" payment scheme with a 300-second timeout.
The broader platform advertises additional endpoints for sentiment analysis, text summarization, classification, embeddings, price feeds, exchange rates, token quotes, gas estimates, geocoding, validation, conversion, and generation — all at the same $0.02/request price point. Documentation pages (docs, pricing, README) returned minimal content (only a "Connect wallet" prompt), so detailed request/response schemas and parameter documentation are unavailable. The endpoint is confirmed live via a valid 402 challenge response.
Capabilities
Use cases
- —Accessing premium API endpoints without sign-up or API key management
- —Making one-off data or AI inference requests with per-call USDC micropayments
- —Integrating pay-as-you-go analytics, finance, or utility services into agent workflows
- —Querying crypto gas estimates or token quotes with instant crypto settlement
Fit
Best for
- —Developers wanting zero-friction API access without subscriptions
- —AI agents that can settle x402 payments autonomously on Base
- —Projects needing low-cost per-request pricing ($0.02) for diverse API calls
Not for
- —Users who need detailed API documentation or OpenAPI schemas before integrating
- —High-volume use cases where subscription-based pricing would be more economical
- —Teams that cannot transact in USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/stripe/charges/179 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is confirmed live with a valid x402 402 challenge, and the landing page provides a catalog of endpoints with pricing. However, there is no OpenAPI schema, no request/response documentation, no examples, and all docs/pricing/README pages return only a wallet-connect prompt. The specific purpose of the '/api/v1/stripe/charges/179' endpoint beyond 'Premium API Access' is unclear.
Warnings
- —No OpenAPI or schema documentation available for any endpoint
- —Docs, pricing, and README pages return only 'Connect wallet' with no actual content
- —The specific functionality of /api/v1/stripe/charges/179 is undocumented — 'Premium API Access' is vague
- —No request body schema or response format is documented anywhere
- —The endpoint path includes 'stripe/charges' which is unusual for an x402 endpoint and its purpose is unclear
Citations
- —The endpoint returns a valid x402 402 challenge with USDC on Base networkhttps://lowpaymentfee.com/api/v1/stripe/charges/179
- —maxAmountRequired is 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913), equaling $0.02https://lowpaymentfee.com/api/v1/stripe/charges/179
- —Platform advertises $0.02/request pricing with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —Platform lists endpoints across data/analytics, AI/ML, finance/Web3, and infrastructure categorieshttps://lowpaymentfee.com