Japanese Corporate Number Lookup: Houjin Bangou (法人番号) API for AI Agents

Every Japanese legal entity has a 13-digit corporate number (法人番号) issued by the National Tax Agency. It's required for B2B invoicing, KYC, and Due Diligence. The NTA publishes the data but only via XML and Japanese-only documentation. Torify wraps it in a clean English REST API.

Endpoint

GET https://torify.dev/v1/houjin/lookup

Parameters

Name	Type	Required	Description	Example
`number`	string	Yes	13-digit Japanese corporate number (法人番号)	`8010401050783`

Response example

{
  "ok": true,
  "data": {
    "number": "8010401050783",
    "name": "...",
    "address": "...",
    "status": "active",
    "confidence": 0.99
  }
}

Code examples

curl

curl "https://torify.dev/v1/houjin/lookup?number=8010401050783"

TypeScript (x402-fetch)

import { wrapFetchWithPayment } from 'x402-fetch';
import { privateKeyToAccount } from 'viem/accounts';

const account = privateKeyToAccount(process.env.PRIVATE_KEY as `0x${string}`);
const fetchWithPayment = wrapFetchWithPayment(fetch, account);

const res = await fetchWithPayment(
  'https://torify.dev/v1/houjin/lookup?number=8010401050783'
);
const data = await res.json();
console.log(data); // { ok: true, data: { ... } }

Python (requests)

import requests

# Free MCP tier (no auth) or API key (X-API-Key header)
res = requests.get(
    "https://torify.dev/v1/houjin/lookup?number=8010401050783",
    headers={"X-API-Key": "your_torify_pro_key"}
)
print(res.json())

Use cases

B2B CRM auto-filling Japanese company information

Pipedrive, HubSpot, Salesforce users enter just the 13-digit 法人番号 and Torify returns the canonical company name, address, and active status — eliminating manual data entry.

Compliance / KYC for fintech onboarding Japanese B2B customers

When a Japan-based merchant signs up, automated KYC verifies the 法人番号 is valid and the company is active. Torify returns confidence scores for cancelled or dissolved entities.

AI agent processing Japanese invoices and contracts

Agents reading invoices need to confirm the issuing company matches the 法人番号 on file. Torify returns both name and address for cross-validation against invoice content.

Edge cases & gotchas

法人番号 has a check digit at position 1 (leftmost). Format-level validation should verify this before hitting the NTA API.
The NTA API has aggressive rate limits (~10 req/sec). Torify caches results for 24 hours to stay within limits and improve latency.
Cancelled / dissolved companies still return their old data with a "status": "closed" flag. Always check the status field before treating data as current.

Related endpoints

/v1/industry/lookup — Japan Industry Code Lookup: JSIC API
/v1/invoice/validate — Japan Invoice Number Format Validation API
/v1/invoice/verify — Japan Invoice Verification: Qualified Invoice (T-Number) API
/v1/tax/calculate — Japan Consumption Tax Calculation API

← All 36 endpoints

Pricing

$0.02 per call via x402 (USDC on Base). Or use a Pro API key ($49/mo, 10,000 calls/month).

View pricing Code examples ↗