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Launching the Lunio Developer API for Canadian Tax Calculations

The Lunio Developer API helps Canadian developers integrate GST, HST, PST, and QST calculations into SaaS platforms, ecommerce systems, invoicing tools, and internal finance workflows.

Launching the Lunio Developer API for Canadian Tax Calculations

Introducing the Lunio Developer API

Canadian tax logic is frustrating to build correctly.

Between GST, HST, PST, and QST differences across provinces and territories, even simple invoice calculations can become messy fast. Most APIs are either too enterprise-focused, too expensive, or built primarily for U.S. tax workflows.

That is why we built the Lunio Developer API.

The Lunio Developer API provides a simple way for developers to integrate Canadian tax calculations directly into their apps, SaaS products, e-commerce systems, invoicing tools, and internal finance workflows.


What the API Currently Supports

The Lunio Developer API currently supports:

  • GST, HST, PST, and QST calculations
  • Province-aware tax logic
  • Reverse tax calculations
  • Secure API key authentication
  • Usage tracking
  • Developer dashboards
  • Interactive API documentation
  • Free and paid request tiers

Current endpoints include:

  • GET /tax/rates
  • POST /tax/calculate
  • POST /tax/reverse

Built for Real Canadian Workflows

The API was designed specifically for Canadian workflows, including:

  • Invoice builders
  • SaaS billing systems
  • E-commerce checkout previews
  • Internal accounting tools
  • Client portals
  • Finance dashboards

Instead of rebuilding provincial tax logic every time, developers can integrate a predictable JSON API and move faster.


Security and API Key Management

The Lunio Developer API includes secure API key handling with:

  • One active API key per account
  • Regenerate and revoke support
  • Usage tracking
  • One-time key reveal for improved security

API keys are treated similarly to passwords and are never permanently exposed after creation.


Developer Dashboard and Documentation

We also launched a dedicated Developer Portal with:

  • Interactive API docs
  • Language examples
  • Usage monitoring
  • Plan management
  • API key controls

The goal is to keep the experience simple, clean, and approachable for indie developers and growing Canadian businesses.


Pricing

The Lunio Developer API currently includes three request tiers:

Free

100 requests/month

Starter

5,000 requests/month

Growth

25,000 requests/month

All plans include access to the same core endpoints.


What’s Next

This is only the beginning.

Future improvements may include:

  • Expanded tax metadata
  • Better reporting endpoints
  • Webhooks
  • SDKs and helpers
  • Additional developer tooling
  • More advanced finance infrastructure for Canadian businesses

Try the Lunio Developer API

You can explore the documentation and generate your API key today.

We’re excited to continue improving the platform and building tools focused specifically on Canadian businesses and developers.

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