USD/SEK forex rate via x402 micropayment on Base for $0.02 per request.
What it does
This endpoint provides the USD/SEK foreign exchange rate through an x402-enabled API hosted at lowpaymentfee.com. Each request costs $0.02 (20,000 base units of USDC on the Base network, where USDC uses 6 decimals). Payment is handled inline via the x402 protocol — no API keys, accounts, or rate limits are required. The caller simply includes an X-PAYMENT header with a valid payment proof.
The endpoint is part of a broader suite of APIs offered by lowpaymentfee.com spanning data analytics, AI/ML inference, finance/crypto data, and utility services, all priced uniformly at $0.02 per request. The forex endpoint specifically targets the USD to Swedish Krona (SEK) currency pair. The response MIME type is application/json.
Documentation on the site is extremely sparse — the docs, pricing, API, 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 endpoint is confirmed live (returns a proper 402 x402 challenge), but the actual response format after payment is unknown.
Capabilities
Use cases
- —Fetching the current USD/SEK exchange rate for financial applications
- —Integrating real-time forex data into trading bots or dashboards
- —Currency conversion calculations for e-commerce or invoicing in SEK
- —Agent-driven forex lookups without pre-registration or API keys
Fit
Best for
- —Agents or apps needing on-demand USD/SEK rates without signup
- —Micropayment-native workflows on Base L2
- —Low-friction, pay-per-call forex data access
Not for
- —High-frequency trading requiring sub-second latency guarantees (no SLA documented)
- —Users needing comprehensive multi-pair forex feeds in a single call
- —Applications requiring detailed historical forex data or OHLC candles
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/forex/USDSEK \
-H "X-PAYMENT: <x402-payment-proof>" \
-H "Content-Type: application/json"Endpoint
Quality
The endpoint is confirmed live via a valid 402 x402 challenge, and pricing is clear ($0.02 USDC on Base). However, there is no OpenAPI spec, no documented request/response schema, no usage examples, and the docs pages are empty. The listing is essentially a stub with only the payment challenge and landing page to work from.
Warnings
- —No API documentation available — docs, pricing, API, and README pages all show only 'Connect wallet' with no content.
- —No request or response schema documented; actual response format after payment is unknown.
- —No OpenAPI or machine-readable spec found.
- —The specific forex endpoint /api/v1/forex/USDSEK is not listed on the landing page's available APIs, though similar finance endpoints are.
Citations
- —The endpoint returns a 402 x402 challenge with maxAmountRequired of 20000 base units of USDC on Base network.https://lowpaymentfee.com/api/v1/forex/USDSEK
- —USDC asset address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base network.https://lowpaymentfee.com/api/v1/forex/USDSEK
- —All APIs on the site are priced at $0.02 per request with no API keys, no rate limits, and instant access.https://lowpaymentfee.com
- —Finance & Web3 category includes price feeds and exchange rates endpoints.https://lowpaymentfee.com