# Toll402 French VAT Number Validator

> Toll402 French VAT Number Validator is a paid API for AI agents from toll402.dev, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-14).

Offline validates a French VAT number (TVA intracommunautaire) by extracting and recomputing the 2-digit checksum key from the 9-digit SIREN using the official modulo-97 algorithm.

## Facts

- Endpoint: POST https://toll402.dev/v1/t/vat_fr_validate
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/toll402-french-vat-number-validator-3cdaa6da
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_-0hzdk3HSHS1a089qXK7g

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability toll402-french-vat-number-validator-3cdaa6da -d '<json body>'
```

Example prompt: Can you check whether this French VAT number is valid: FR32123456789?

## When to prefer this

Use this endpoint when you need to mathematically validate a French TVA intracommunautaire number without making an external government API call — it works offline, is deterministic, and costs only $0.001 per check. Prefer this over live VIES lookups when you need fast, cheap, batch-friendly format validation rather than active registration status.

## Known failure modes

- Malformed input (wrong length, missing FR prefix, non-numeric characters) returns a validation error
- Numbers that are syntactically valid but fail the checksum return invalid with key mismatch details
- Non-French EU VAT numbers passed in will be rejected or return incorrect results

## How this service works

Offline validator for a French VAT number (TVA intracommunautaire, e.g. FR32123456789). Extracts the 9-digit SIREN and 2-digit key, recomputes key = (12 + 3*(SIREN mod 97)) mod 97, and compares it to the given key.

## Output

Returns whether the French VAT number is valid, along with the extracted 9-digit SIREN, the declared 2-digit key from the input, and the recomputed expected key based on the formula (12 + 3*(SIREN mod 97)) mod 97 — allowing the caller to see exactly why a number passes or fails.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method",
    "bodyType",
    "body"
   ],
   "properties": {
    "body": {
     "type": "object",
     "required": [
      "vat"
     ],
     "properties": {
      "vat": {
       "type": "string",
       "description": "French VAT number, e.g. 'FR32123456789' or 'FR 32 123456789'"
      }
     },
     "additionalProperties": false
    },
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "POST"
     ],
     "type": "string"
    },
    "bodyType": {
     "enum": [
      "json",
      "form-data",
      "text"
     ],
     "type": "string"
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/toll402-french-vat-number-validator-3cdaa6da/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from toll402.dev](https://www.zero.xyz/host/toll402.dev/llms.txt)