fourzerotwo-si Vat API
VAT Rates & Checks: UK and EU27 VAT rates, net↔gross VAT maths, and VAT-number format and check-digit validation.
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OpenAPI Specification
openapi: 3.2.0
info:
title: Fourzerotwo Si Vat API
version: 1.1.0
contact:
url: https://fourzerotwo.si
description: 'Operations tagged vat across 2 of this provider''s published API definitions: openapi.json, fourzerotwo-si-openapi.json. Each path carries the servers of the definition it was published in.'
servers:
- url: https://fourzerotwo.si
tags:
- name: vat
description: 'VAT Rates & Checks: UK and EU27 VAT rates, net↔gross VAT maths, and VAT-number format and check-digit validation.'
paths:
/v1/vat/rates:
get:
operationId: vat__rates
summary: 'VAT Rates & Checks: VAT rates'
description: 'Standard, reduced and super-reduced VAT rates for one country or all of EU27 + UK, with the date they were checked. Price: $0.001 USDC per call via x402. Free within the daily allowance with a free key.'
tags:
- vat
externalDocs:
url: https://fourzerotwo.si/apis/vat/rates
parameters:
- name: country
in: query
required: false
description: ISO code (omit for all)
schema:
type: string
maxLength: 2
example: FR
responses:
'200':
description: The data (paid, or free tier).
content:
application/json: {}
'402':
$ref: '#/components/responses/PaymentRequired'
'400':
$ref: '#/components/responses/Error'
'404':
$ref: '#/components/responses/Error'
'502':
$ref: '#/components/responses/Error'
security:
- {}
- freeKey: []
x-price-usd: '0.001000'
x-free-tier: free
x-mcp-tool: vat__rates
servers:
- url: https://fourzerotwo.si
/v1/vat/calculate:
get:
operationId: vat__calculate
summary: 'VAT Rates & Checks: Add or remove VAT'
description: 'Net to gross or gross to net at a given rate, or at a country''s standard rate. Price: $0.001 USDC per call via x402. Free within the daily allowance with a free key.'
tags:
- vat
externalDocs:
url: https://fourzerotwo.si/apis/vat/calculate
parameters:
- name: amount
in: query
required: true
description: Amount
schema:
type: string
maxLength: 20
example: '100'
- name: rate
in: query
required: false
description: VAT rate in percent (or give country)
schema:
type: string
maxLength: 6
- name: country
in: query
required: false
description: Use this country's standard rate
schema:
type: string
maxLength: 2
example: GB
- name: from
in: query
required: false
description: net (default) or gross
schema:
type: string
maxLength: 5
example: net
responses:
'200':
description: The data (paid, or free tier).
content:
application/json: {}
'402':
$ref: '#/components/responses/PaymentRequired'
'400':
$ref: '#/components/responses/Error'
'404':
$ref: '#/components/responses/Error'
'502':
$ref: '#/components/responses/Error'
security:
- {}
- freeKey: []
x-price-usd: '0.001000'
x-free-tier: free
x-mcp-tool: vat__calculate
servers:
- url: https://fourzerotwo.si
/v1/vat/validate-format:
get:
operationId: vat__validate_format
summary: 'VAT Rates & Checks: Validate a VAT number format'
description: 'Country format and check digit for UK (GB/XI) and EU VAT numbers. Does not confirm registration. Price: $0.001 USDC per call via x402. Free within the daily allowance with a free key.'
tags:
- vat
externalDocs:
url: https://fourzerotwo.si/apis/vat/validate-format
parameters:
- name: vat_number
in: query
required: true
description: VAT number with country prefix
schema:
type: string
maxLength: 20
example: GB980780684
responses:
'200':
description: The data (paid, or free tier).
content:
application/json: {}
'402':
$ref: '#/components/responses/PaymentRequired'
'400':
$ref: '#/components/responses/Error'
'404':
$ref: '#/components/responses/Error'
'502':
$ref: '#/components/responses/Error'
security:
- {}
- freeKey: []
x-price-usd: '0.001000'
x-free-tier: free
x-mcp-tool: vat__validate-format
servers:
- url: https://fourzerotwo.si
components:
responses:
PaymentRequired:
description: x402 payment required. The body (also base64 in the PAYMENT-REQUIRED header) lists accepted payments.
headers:
PAYMENT-REQUIRED:
schema:
type: string
description: Base64 JSON x402 v2 PaymentRequired
content:
application/json:
schema:
type: object
properties:
x402Version:
type: integer
error:
type: string
accepts:
type: array
items:
type: object
Error:
description: 400 = invalid input, 404 = not found at the source, 502 = the source failed. Never charged.
content:
application/json:
schema:
type: object
properties:
error:
type: string
charged:
type: boolean
securitySchemes:
freeKey:
type: apiKey
in: header
name: X-API-Key
description: Optional free key (fzt_…) for the free tier.
x-refined-from:
- openapi.json
- fourzerotwo-si-openapi.json