⚡Flash402Console →
Live on Base Sepolia · powered by the x402 protocol

Turn any API into a pay-per-call endpoint

Paste a URL, set a price, share a link. Flash402 puts an onchain USDC paywall in front of your API over HTTP 402 — no accounts, no API keys, no code changes.

Monetize an APIWatch it get paid ↓

402 Payment Required → sign → 200 OK · settled in USDC

GET /api/gw/<id> — live payment trace
1 · unpaid requestHTTP 402
{
  "x402Version": 2,
  "error": "Payment required",
  "accepts": [{
    "scheme": "exact",
    "network": "eip155:84532",
    "amount": "10000",
    "asset": "0x036C…F7e (USDC)",
    "payTo": "0x1111…1111"
  }]
}
2 · paid requestHTTP 200
{
  "amount": 1,
  "base": "USD",
  "date": "2026-07-02",
  "rates": { "EUR": 0.87727 }
}
// ↑ upstream response, unlocked
//   after 0.01 USDC settled onchain

Real trace from a Base Sepolia payment — the caller paid, the facilitator settled, the API answered.

From free API to paid in 3 steps

See it in action

Watch a plain API become a paid, onchain-settled endpoint in one flow.

Made for the agent economy

⚡

Zero code

A proxy sits in front of your API — no SDK, no rewrite, your endpoint's behaviour is untouched.

🔗

Onchain settlement

Payments settle in USDC on Base via the x402 facilitator. No middleman account.

🪙

True pay-per-call

No subscriptions, no tiers. Callers pay for exactly the requests they make.

🤖

Agent-ready

AI agents pay programmatically over HTTP 402 — the native rail for agentic commerce.

📊

Live earnings

Every paid call is counted, so you always see what each endpoint is making.

🌐

Any endpoint

Path, query and method are forwarded through untouched to your upstream.

FAQs

An open standard that revives the HTTP 402 status code so a client can pay for a request in stablecoin — no accounts, no API keys. Flash402 puts that flow in front of your existing API.

No code changes. Flash402 proxies requests untouched — path, query and method are forwarded as-is, your endpoint's behaviour stays identical. The only thing you add is a one-time DNS TXT record to prove you own the domain (and even that's skipped for the demo APIs).

Only APIs on a domain you control — you prove it with a single DNS TXT record (no deploy), so nobody can charge for an API that isn't theirs. Just want to try it? A few public demo APIs are allowlisted, so you can run the whole flow without owning anything.

No. The caller signs an EIP-3009 authorization (just a signature, no gas). The x402 facilitator submits it on-chain and covers the gas — the caller only spends the USDC price.

A wallet with USDC on Base. No sign-up and no API key — a human clicks and signs, or an AI agent pays programmatically over x402.

USDC on Base. This build runs on Base Sepolia testnet so you can try it for free; flipping one env var points it at Base mainnet.

Yes — that's the point. Agents pay per request over x402 without managing keys or gas, which is exactly what agentic commerce needs.

Put a price on your API in 30 seconds

Spin up a gateway, run a real testnet payment, and watch the USDC land.

Launch the console →