VAT Sense - Free UK & EU VAT Number Validation API, EU VAT rates API

# VAT Sense > Developer-friendly REST API for VAT/GST compliance. Validate VAT and EORI numbers, look up VAT/GST rates by country or product type, convert currencies, and generate VAT-compliant invoices. Used by Oracle, Siemens, and thousands of developers worldwide. Sub-15ms response times, 99.9%+ uptime, 256-bit SSL on all plans including free. AI agents can obtain a temporary sandbox API key to test VAT Sense without creating an account. See the [full documentation](https://vatsense.com/llms-full.txt) for details, or POST to `https://api.vatsense.com/1.0/sandbox/key` to get a key immediately. ## Documentation - [Full API documentation for LLMs](https://vatsense.com/llms-full.txt): Complete API reference in a single document - [OpenAPI specification](https://vatsense.com/openapi.yaml): Machine-readable OpenAPI 3.0 spec (importable into Postman, Insomnia, etc.) - [Postman collection](https://www.postman.com/vatsense/vat-sense-api/collection/7415051-77f802c0-ba4d-4456-8d01-f3a4dc222604): Pre-built collection with all API endpoints, ready to fork and use - [API Reference](https://vatsense.com/documentation): Full API docs covering authentication, endpoints, and code examples - [API Reference - Authentication](https://vatsense.com/documentation#authentication): HTTP Basic Auth setup - [API Reference - Rates](https://vatsense.com/documentation#rates): VAT/GST rate lookups by country, IP, or product type - [API Reference - Countries](https://vatsense.com/documentation#countries): Country and province data - [API Reference - Validate](https://vatsense.com/documentation#validate): VAT and EORI number validation - [API Reference - Currency](https://vatsense.com/documentation#currency): Currency conversion with HMRC and ECB rates - [API Reference - Invoices](https://vatsense.com/documentation#invoices): VAT-compliant invoice CRUD - [API Reference - Invoice items](https://vatsense.com/documentation#invoice_items): Invoice line item management ## Official libraries and S

openapi: 3.0.3 info: title: VAT Sense API description: | Developer-friendly REST API for VAT/GST compliance. VAT Sense helps businesses selling internationally with VAT number validation, VAT/GST rate lookups, currency conversion, country data, and VAT-compliant invoicing. ## Authentication All API requests require authentication via HTTP Basic Auth: - **Username:** `user` - **Password:** Your API key All requests must be made over HTTPS. Requests made over