Pay-per-call API platform on Base network via x402 — $0.02/request in USDC.
What it does
lowpaymentfee.com is an x402-enabled API platform that offers a variety of endpoints across data analytics, AI/ML inference, finance/Web3, and infrastructure utilities. All endpoints are pay-per-request using the x402 protocol, settling payments in USDC on the Base network. The specific endpoint at `/api/v1/charges/179` is labeled "Premium API Access" and accepts POST requests.
The platform advertises a flat $0.02 per request across its listed endpoints, with no API keys, no rate limits, and no minimum commitments required. The x402 challenge captured from this endpoint shows a maxAmountRequired of 20000 base units of USDC (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base), which equals $0.02 given USDC's 6 decimals. Payment is made via the `exact` scheme to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 with a 300-second timeout.
The broader platform lists 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 price point. 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 from the crawled content.
Capabilities
Use cases
- —Agents needing on-demand API access without pre-registration or API keys
- —Programmatic pay-per-call access to data, AI, finance, or utility endpoints
- —Testing x402 protocol integrations with a low-cost endpoint
Fit
Best for
- —Developers exploring x402 payment protocol integrations
- —AI agents that need keyless, pay-as-you-go API access
- —Low-volume consumers who want no subscription commitments
Not for
- —High-volume production workloads requiring detailed SLAs and documentation
- —Users who need well-documented request/response schemas before integrating
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/charges/179 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge, confirming it accepts payments. However, there is no OpenAPI spec, no documented request/response schema, no examples, and the docs/pricing/README pages are all blank beyond a wallet connect prompt. The purpose of this specific '/charges/179' endpoint is unclear beyond the generic 'Premium API Access' label. Effectively a stub listing.
Warnings
- —No OpenAPI or schema documentation available — request body format and response structure are unknown
- —Docs, pricing, API, and README pages all render only 'Connect wallet' with no usable content
- —The specific functionality of /api/v1/charges/179 ('Premium API Access') is not described anywhere
- —No examples of successful responses are available
Citations
- —Platform advertises $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —x402 challenge shows maxAmountRequired of 20000 base units of USDC on Base with exact schemehttps://lowpaymentfee.com/api/v1/charges/179
- —USDC asset address is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/charges/179
- —Docs, pricing, API, and README pages show only 'Connect wallet'https://lowpaymentfee.com/docs