ipv4.fr HTTP headers
HTTP response headers of a public URL (HEAD request, redirects reported, not followed). Maintained by ipv4.fr.
1 route settlement-verified · $0.003 USDC/request · 1 endpoint · Verification · base network · x402 protocol
Verified routes
GET /x402/v1/headers· $0.003 · 2026-10-26 · receipt
Other routes are unverified.
Networks: Base (settlement-verified)
Discovery is free. Agents search the catalogue here. Payment happens on the listing 402, not on PayAPI.
url https://payapi.market/mcpListing facts
- Provider
- ipv4.fr DNS lookup
- Hosted at
ipv4.fr- Category
- Verification
- Price
- $0.003 USDC per request
- Payment networks
- Base
- Settlement-verified
- 1 route, last checked 2026-10-26
- Listed on PayAPI Market
- 2026-10-26
Try ipv4.fr HTTP headers
Call a verified route without paying first. The server should answer HTTP 402 Payment Required with the price, the USDC asset, the network and the wallet to pay. An x402 client pays that amount on Base and retries with the payment header.
curl -i "https://ipv4.fr/x402/v1/headers?url=https://example.com"About this API
ipv4.fr HTTP headers is listed in the Verification category with pricing at $0.003 USDC/request. One route has been settlement-verified by PayAPI Market on 2026-10-26. View receipt on Basescan.
Payments settle on base in USDC via the x402 protocol. AI agents discover this API through the PayAPI Market MCP server and pay per request without API keys or accounts.
This API exposes 1 endpoint.
Questions about this API
What does ipv4.fr HTTP headers do?
HTTP response headers of a public URL (HEAD request, redirects reported, not followed). Maintained by ipv4.fr. It is provided by ipv4.fr DNS lookup.
How much does ipv4.fr HTTP headers cost?
ipv4.fr HTTP headers is priced at $0.003 USDC per request, paid per call with no subscription. PayAPI Market paid 0.003 USDC for one call to /x402/v1/headers when it verified the listing. The exact amount for each call is in the HTTP 402 response before any money moves.
Do I need an API key or account to use ipv4.fr HTTP headers?
No. ipv4.fr HTTP headers uses the x402 protocol, so an agent pays per request in USDC on Base and gets the response, with no API key, account or signup.
Has ipv4.fr HTTP headers been verified?
Yes, 1 route. PayAPI Market paid for a real call from its own wallet, received real data back and recorded the USDC settlement on-chain, most recently on 2026-10-26.
How does an AI agent find ipv4.fr HTTP headers?
Through the free PayAPI Market MCP server at https://payapi.market/mcp, using search_apis or get_api, or over plain HTTP at https://payapi.market/agent/search. Discovery is free; the agent pays the provider directly on the listing's own 402.
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