FinzBooks API

A GST-first, REST + JSON API for Indian SMB bookkeeping — invoices, bills, payments, contacts, reports, webhooks. Same operations as the FinzBooks dashboard, scriptable from any language.

Where to start

• Quickstart — mint a token and make your first call in under five minutes.
• Authentication — PATs vs OAuth, scopes, multi-org tokens.
• Full API Reference — every endpoint with Try-It-Out.

Core concepts

Cross-cutting behaviour every endpoint inherits. Read once, applies everywhere.

• Response envelope — the consistent shape every list and single-resource response uses.
• Pagination — opaque cursors, forward walking.
• Idempotency — safe retries via the Idempotency-Key header.
• Errors — string error codes you can switch on.
• Rate limits — 600 / 3,000 req per minute tiers.

Integrations

• OAuth 2.0 — partner-app flow with PKCE, refresh tokens, replay detection.
• Webhooks — signed JSON event deliveries.

Ready to build? Get an API token