What is Fluxrate?
Fluxrate is a comprehensive billing platform that gives engineering teams the primitives they need to implement any pricing model — without rebuilding 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.Quickstart
Get your first usage event tracked in under 5 minutes.
Core Concepts
Understand meters, plans, subscriptions, and how they connect.
API Reference
Full REST API documentation with examples.
SDK Guide
Integrate usage tracking into your backend in minutes.
Key Capabilities
Any Pricing Model
Any Pricing Model
- Fixed — Flat recurring charges billed daily, weekly, monthly, or yearly
- Usage-based — Charge per unit consumed with SUM, MAX, UNIQUE_COUNT, or LAST aggregations
- Hybrid — Combine fixed base fees with metered usage charges on a single plan
- Tiered Pricing — Volume-based pricing tiers for usage charges
Real-time Usage Metering
Real-time Usage Metering
Create custom meters (API calls, storage, tokens, seats, etc.) and track usage events in real time. Query aggregated data by customer, subscription, or time period.
Automated Invoicing
Automated Invoicing
Invoices are generated automatically when subscription periods end. A 1-hour grace period gives you time to review before invoices are finalized and emailed to customers.
Feature Entitlements
Feature Entitlements
Control exactly what each plan unlocks — meter-based limits, boolean feature flags, or custom entitlement values. Plans are composed of features and charges.
Multi-tenant & Secure
Multi-tenant & Secure
Full organization-level data isolation, JWT authentication with HttpOnly cookies, scoped API keys for SDK integration, and Fernet encryption for sensitive data.
Customer Portal
Customer Portal
Embed a customer-facing portal in your product so your customers can view invoices and usage without leaving your app.
How It Works
- Define Meters — Create usage meters that define what to track (e.g.,
api_calls,storage_gb,active_users). - Build Features — Wrap meters in features with entitlement rules (limits, resets, on/off flags).
- Create Plans — Combine features and charges (fixed and/or usage-based) into billing plans.
- Subscribe Customers — Assign customers to plans with a start date and billing interval.
- Track Usage — Send usage events via the SDK or REST API.
- Invoicing — Fluxrate automatically computes usage, generates invoices, and emails them.
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 | 0.005/GB storage |
| Tiered | Volume brackets for usage | First 1,000 calls free, then $0.001 each |
Next Steps
Quickstart
Track your first usage event in 5 minutes
SDK Integration
Add Fluxrate to your backend