> ## Documentation Index
> Fetch the complete documentation index at: https://docs.cleariflow.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Introduction

> Cleariflow VAT Validation API delivers comprehensive tax compliance solutions through a streamlined, contemporary RESTful JSON interface, enabling seamless validation and calculation for domestic and international business operations.

## Getting started

<Card title="Validate VAT endpoint" icon="tag" href="vat/validate">
  Verify VAT number authenticity and retrieve comprehensive company information including country, business name, address, and registration details.
</Card>

<Card title="Calculate VAT endpoint" icon="tags" href="vat/calculate">
  Compute VAT-compliant pricing based on country-specific regulations, purchase type, and transaction value for accurate financial calculations.
</Card>

<Card title="VAT Categories endpoint" icon="globe" href="vat/categories">
  Access current VAT rates and tax categories for specific countries to ensure compliance with local tax regulations.
</Card>

### REST Architecture

The VAT Validation API follows REST principles, utilizing predictable resource-oriented URLs and standard HTTP status codes for seamless integration and error handling. All API endpoints must end with a trailing slash (/) and support only GET requests.

### HTTPS Security

All API communications are secured using TLS 1.2 or higher encryption protocols to ensure data integrity and privacy.

### API Versioning

The VAT Validation API maintains backward compatibility through versioning, currently operating on Version 1 with planned future enhancements.

### Authentication

Your API key serves as the exclusive credential for accessing the VAT Validation API. Each Cleariflow service requires a unique key, ensuring secure and isolated access across different APIs. The API implements rate limiting to ensure fair usage across all users.

## Response and error codes

When requests fail, the API returns structured JSON error responses with specific codes and descriptions for effective troubleshooting.

| Code | Type                  | Details                                                                                                                                                     |
| ---- | --------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------- |
| 200  | OK                    | Everything worked as expected.                                                                                                                              |
| 400  | Bad request           | Bad request.                                                                                                                                                |
| 401  | Unauthorized          | The request was unacceptable. Typically due to the API key missing or incorrect.                                                                            |
| 422  | Quota reached         | The request was aborted due to insufficient API credits.  (Free plans)                                                                                      |
| 429  | Too many requests     | The request was aborted due to the number of allowed requests per second being reached. This happens on free plans as requests are limited to 1 per second. |
| 500  | Internal server error | The request could not be completed due to an error on the server side.                                                                                      |
| 503  | Service unavailable   | The server was unavailable.                                                                                                                                 |

## Country codes

Below are the list of countries supported by the VAT endpoints

| Country code | Country name    |
| ------------ | --------------- |
| AT           | Austria         |
| BE           | Belgium         |
| BG           | Bulgaria        |
| CY           | Cyprus          |
| CZ           | Czech Republic  |
| DE           | Germany         |
| DK           | Denmark         |
| EE           | Estonia         |
| FI           | Finland         |
| FR           | France          |
| GB           | United Kingdom  |
| GR           | Greece          |
| HR           | Croatia         |
| HU           | Hungary         |
| IE           | Ireland         |
| IT           | Italy           |
| LT           | Lithuania       |
| LU           | Luxembourg      |
| LV           | Latvia          |
| MT           | Malta           |
| NL           | The Netherlands |
| PL           | Poland          |
| PT           | Portugal        |
| RO           | Romania         |
| SE           | Sweden          |
| SI           | Slovenia        |
| SK           | Slovakia        |