> ## Documentation Index
> Fetch the complete documentation index at: https://docs.fluxrate.co/llms.txt
> Use this file to discover all available pages before exploring further.

# Introduction

> Fluxrate is a developer-first billing infrastructure for SaaS companies supporting fixed, usage-based, and hybrid pricing out of the box.

## What is Fluxrate?

Fluxrate is a comprehensive billing platform that gives engineering teams the primitives they need to implement any pricing model without building billing logic from scratch.

Whether you charge a flat monthly fee, bill per API call, or combine both in a hybrid plan, Fluxrate handles the metering, subscription lifecycle, invoice generation, and customer management so you can focus on your product.

## Product Capabilities

<AccordionGroup>
  <Accordion title="Any Pricing Model" icon="dollar-sign">
    * **Fixed** - Flat recurring charges billed daily, weekly, monthly, or yearly
    * **Usage-based** - Charge per unit consumed with different calculation logics
    * **Hybrid** - Combine Fixed base fees and  Usage charges on a single plan
    * **Tiered Pricing** - Volume-based pricing tiers for usage charges
  </Accordion>

  <Accordion title="Real-time Usage Analytics" icon="chart-line">
    Create  metered feature to track (API calls, storage, tokens, seats, etc.) and insight on customer usage realtime.
  </Accordion>

  <Accordion title="Automated Invoicing" icon="file-invoice">
    Invoices are generated automatically based on subscriptions. Providing invoice link with custom branding.
  </Accordion>

  <Accordion title="Features (Entitlements)" icon="badge-check">
    Control exactly what each plan unlocks meter-based limits, boolean feature flags, or custom entitlement values.
  </Accordion>

  <Accordion title="Customer Portal" icon="users">
    Embed a customer-facing portal in your product so your customers can view invoices and usage.
  </Accordion>
</AccordionGroup>

## How It Works

1. **Define Features** - Create metered feature that define what to track (e.g., `api_calls`, `storage_gb`, `active_users`), Boolean & Custom value featured.
2. **Create Plans** - Combine features with limit and add Flat and Usage based charges with overages.
3. **Subscribe Customers** - Assign customers to plans with a start date and billing interval.
4. **Track Usage** - Send usage events via the SDK or REST API.
5. **Invoicing** - Fluxrate automatically computes usage, generates invoices, and emails to your customers.
6. **Payments** - Fluxrate provide multiple payment gateway integration that suits your business need.

## Pricing Models Supported

| **Model**       | **Description**                         | **Example**                               |
| :-------------- | :-------------------------------------- | :---------------------------------------- |
| **Fixed**       | Flat recurring fee                      | \$99/month SaaS subscription              |
| **Usage-based** | Pay per unit consumed                   | \$0.001 per API call                      |
| **Hybrid**      | Fixed + usage combined                  | \$49/month (Fixed) + \$0.005/GB storage   |
| **Tiered**      | Volume and graduated brackets for usage | First 1,000 calls free, then \$0.001 each |

## Next step

<CardGroup cols={2}>
  <Card title="Quickstart" icon="rocket" href="/quickstart">
    Get your first usage event tracked in under 5 minutes.
  </Card>

  <Card title="API Reference" icon="code" href="/api-reference/introduction">
    Full REST API documentation with examples.
  </Card>

  <Card title="SDK Guide" icon="cube" href="/developers/sdk/overview">
    Integrate usage tracking into your backend in minutes.
  </Card>

  <Card title="Integrations" icon="code-fork" href="/integrations/overview">
    Explore native integrations for you business.
  </Card>
</CardGroup>