Developer documentation

Integrate customs-invoice.com

Send shipment JSON, get back compliant PDF URLs. Designed for embedding into Shopify apps, freight-forwarder dashboards, ShipStation / Shippo workflows, or bespoke internal tooling.

Quickstart

Ship your first invoice through the API in five minutes — key, request, PDF.

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API reference

Endpoints, request / response schemas, code samples in curl / Node / Python.

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Error reference

Every error code the API can return and how to recover from it.

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Changelog

Additive-first API evolution. No breaking changes without a version bump.

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Core concepts

  • Invoices — a single call creates one shipment record and renders 1–4 PDFs (commercial or proforma, plus optional packing list and certificate of origin).
  • Signed URLs — responses contain one-hour signed URLs per document. Persist the PDFs on your side rather than relying on long-lived links.
  • Bearer auth — every key is 48 hex characters with a cik_ prefix. Keys are stored as SHA-256 digests; we can't recover a lost key.
  • Rate limits — 60 invoices per hour per key. Heavier throughput available by request.