# Lago — Open Source Usage-Based Billing API

> Lago is an open-source metering and billing engine for usage-based pricing, subscription management, invoicing, and payment orchestration.

## Install

Save the content below to `.claude/skills/` or append to your `CLAUDE.md`:

## Quick Use

```bash
git clone https://github.com/getlago/lago.git
cd lago
docker compose up -d
```

Open `http://localhost:80` — access the Lago dashboard to configure billing plans and meters.

## Intro

**Lago** is an open-source billing API for usage-based pricing models. It handles metering, subscription management, invoicing, and payment orchestration — replacing expensive SaaS billing platforms like Stripe Billing, Chargebee, or Zuora for companies that need flexibility and control.

With 9.5K+ GitHub stars and AGPL-3.0 license, Lago powers billing for AI companies, API platforms, and SaaS products that charge based on consumption (API calls, tokens, compute hours, storage).

## What Lago Does

Lago provides the complete billing infrastructure:

- **Usage Metering**: Ingest events via API, aggregate by count, sum, max, unique count, or weighted sum
- **Flexible Pricing**: Per-unit, graduated, package, percentage, and volume-based pricing models
- **Subscription Management**: Create plans with recurring charges, add-ons, and trial periods
- **Real-Time Invoicing**: Automatic invoice generation with PDF export and tax calculation
- **Payment Orchestration**: Integrate with Stripe, GoCardless, Adyen for automatic payment collection
- **Revenue Analytics**: Track MRR, churn, lifetime value, and usage trends
- **Webhooks**: Real-time events for invoice created, payment succeeded/failed, subscription changes
- **Multi-Currency**: Support for 150+ currencies with automatic conversion

### Ingesting Usage Events

```bash
# Send a usage event via API
curl -X POST https://api.lago.dev/api/v1/events \
  -H "Authorization: Bearer $LAGO_API_KEY" \
  -H "Content-Type: application/json" \
  -d "{
    \"event\": {
      \"transaction_id\": \"tx_001\",
      \"external_subscription_id\": \"sub_123\",
      \"code\": \"api_calls\",
      \"timestamp\": $(date +%s),
      \"properties\": {
        \"tokens\": 1500
      }
    }
  }"
```

### Python SDK

```python
from lago_python_client import Client

client = Client(api_key="lago_api_key")

# Create a billable metric
client.billable_metrics.create({
    "name": "API Calls",
    "code": "api_calls",
    "aggregation_type": "sum_agg",
    "field_name": "tokens"
})

# Create a plan with usage-based pricing
client.plans.create({
    "name": "Pro Plan",
    "code": "pro",
    "interval": "monthly",
    "amount_cents": 4900,
    "charges": [{
        "billable_metric_code": "api_calls",
        "charge_model": "graduated",
        "properties": {
            "graduated_ranges": [
                {"from_value": 0, "to_value": 10000, "per_unit_amount": "0.001"},
                {"from_value": 10001, "to_value": None, "per_unit_amount": "0.0005"}
            ]
        }
    }]
})
```

## FAQ

**Q: Is Lago suitable for AI/LLM billing?**
A: Yes. Lago is specifically designed for usage-based billing — track tokens, API calls, compute hours, or any custom metric and bill accordingly.

**Q: How does Lago compare to Stripe Billing?**
A: Lago offers more flexible metering and pricing models, full self-hosting, and no percentage-of-revenue fees. Stripe Billing is easier to start with but less customizable for complex usage-based models.

**Q: Can I self-host Lago?**
A: Yes. Deploy with Docker Compose for a complete setup including PostgreSQL, Redis, and the web dashboard.

**Q: What payment processors does Lago support?**
A: Stripe, GoCardless, and Adyen. Payment collection is automatic based on generated invoices.

## Source & Thanks

- GitHub: [getlago/lago](https://github.com/getlago/lago) — 9.5K+ ⭐ | AGPL-3.0
- Website: [getlago.com](https://www.getlago.com)
- Docs: [docs.getlago.com](https://docs.getlago.com)

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## Quick Use

```bash
git clone https://github.com/getlago/lago.git
cd lago
docker compose up -d
```

Open `http://localhost:80` to access the Lago dashboard and configure billing plans and meters.

## Introduction

**Lago** is an open-source billing API designed for usage-based pricing. It handles metering, subscription management, invoicing, and payment orchestration — replacing expensive SaaS billing platforms like Stripe Billing and Chargebee.

With 9.5K+ GitHub stars and AGPL-3.0 licensing, Lago provides the billing infrastructure for AI companies, API platforms, and consumption-based SaaS products.

## Core Features

- **Usage metering**: Ingest events via API with count, sum, max, and other aggregation modes
- **Flexible pricing**: Per-unit, tiered, package, percentage, and usage-based pricing models
- **Subscription management**: Create plans with recurring fees, add-ons, and trial periods
- **Real-time invoicing**: Auto-generated invoices with PDF export and tax calculation
- **Payment orchestration**: Automated collection via Stripe, GoCardless, and Adyen

## FAQ

**Q: Is Lago suitable for AI/LLM billing?**
A: Yes. Lago is built for usage-based billing and can track tokens, API calls, compute time, or any custom metric.

**Q: Can I self-host?**
A: Yes. Deploy with Docker Compose, including PostgreSQL, Redis, and the web dashboard.

## Source & Thanks

- GitHub: [getlago/lago](https://github.com/getlago/lago) — 9.5K+ ⭐ | AGPL-3.0
- Website: [getlago.com](https://www.getlago.com)

---
Source: https://tokrepo.com/en/workflows/lago-open-source-usage-based-billing-api-f9227c2e
Author: AI Open Source