Validate a US bank routing number (ABA) deterministically: 9-digit check, ABA mo...
Validate a US bank routing number (ABA) deterministically: 9-digit check, ABA mod-10 weighted checksum, Federal Reserve district decode and institution-id extraction. Zero external dependencies, no hallucination, always available. Use it to validate a US bank account before an ACH/wire payment. Complements IBAN validation for international. Ed25519-signed. 0.001 USDC on Base. First 3 calls FREE per wallet — send header X-WALLET: 0x<your Base address> (no payment); then per call.
Start with a quote-only recipe. Payment signing stays in your project.
const response = await fetch("https://routingcheck.hergertsynthora.com/service", {
method: "GET",
});
console.log(response.status);
console.log(Object.fromEntries(response.headers));
console.log((await response.text()).slice(0, 1000));
// A valid 402 is a quote, not a completed paid call.This sends no payment. Inspect the 402 response before adding a wallet-enabled client.
- Live 402 quote confirmed
GET returned a protocol-valid 402 quote (402). No payment was made.
- Origin reachable
HEAD https://routingcheck.hergertsynthora.com/ returned 402.
- Observed in 402-index
Discovered through bazaar.
EVIDENCE
Each record has an exact-route quote outcome. Unresolved templates and potentially mutating methods are labeled instead of being invoked without provider-specific test input. A quote is still separate from a settled paid call.