Xero

Xero API provides comprehensive cloud-based accounting functionality with OAuth 2.0 authentication. Supports 150 endpoints covering invoices, contacts, bank transactions, purchase orders, expenses, credit notes, payments, and financial reporting with JSON responses.

Accounting API includes chart of accounts, multi-currency transactions, tax management, inventory tracking, and payroll integration. Reports API provides balance sheets, profit and loss statements, trial balances, aged payables/receivables, and GST/BAS reports. Flexible filtering with where clauses, date range operators, and pagination support for high-volume queries..

Webhooks enable real-time notifications for invoice and contact changes with signature verification for security. Batch API support for efficient data operations. Attachment support for documents across entities. Rate limiting: 60 calls per minute, 5,000 per day per tenant, with concurrent request limits.

Official SDKs for JavaScript (Node), Python, Java, PHP, C#, and Ruby. Comprehensive developer documentation with sandbox environment for testing. 30-day free trial with subscription required for continued access. Sandbox and production environments. Ideal for accounting integrations, financial management applications, e-commerce platforms, and automated bookkeeping solutions.