# Lago > Lago is the open-source billing platform for usage-based, subscription-based, and hybrid pricing models. Built for AI, SaaS, fintech, IoT, and infrastructure companies that need flexible, high-volume billing without vendor lock-in. Self-host for full control, or use Lago Cloud to get started in minutes. Lago processes up to 1,000,000 billing events per second. It supports every modern pricing model — metered, subscription, prepaid credits, hybrid, entitlements — through a single API-first platform. The codebase is open-source (AGPLv3) and fully auditable. Customers include Mistral AI, PayPal, and Groq. Important notes: - Lago is not a payment processor. It handles billing logic, metering, and invoicing. It integrates with payment processors (Stripe, Adyen, GoCardless, and others). - Lago is not a subscription management tool only. It is a full metering, billing, and revenue platform. - "Plans" in Lago define pricing structure. "Subscriptions" are created when a plan is assigned to a customer. These are distinct concepts. - Lago Cloud and Lago self-hosted use the same codebase. The difference is deployment, not features. ## Core platform - [Homepage](https://getlago.com/): Open-source billing infrastructure for usage-based and hybrid pricing. Trusted by Mistral AI, PayPal, Groq, and others. - [Pricing](https://getlago.com/pricing): Lago's plan tiers — Starter, Growth, and Enterprise. Cloud and self-hosted options available. - [Customers](https://getlago.com/customers): Customer stories and case studies from AI, fintech, SaaS, and infrastructure companies using Lago. - [Security](https://getlago.com/security): SOC 2 Type II, RBAC, SSO, audit logs, and deployment options (cloud, VPC, on-premise). - [Book a demo](https://getlago.com/book-a-demo): Contact Lago's team for a guided demo and trial access. - [About Lago](https://getlago.com/about-us): Company background, founding story, and mission. ## Platform features - [Usage Metering](https://getlago.com/platform/usage-metering): Real-time event ingestion at 1,000,000 events/second. Supports COUNT, SUM, MAX, UNIQUE COUNT, and CUSTOM aggregation types. Idempotency guaranteed via transaction IDs. Billable metrics define how events are aggregated into chargeable units. - [Billing & Invoicing](https://getlago.com/platform/billing-invoicing): Automated invoice generation, multi-currency support, tax handling, PDF invoices, credit notes, and payment collection. Supports calendar and anniversary billing cycles. - [Entitlements](https://getlago.com/platform/entitlements): Feature access management tied directly to billing plans. Define features, attach them to plans, override for individual subscriptions. Eliminates the need for a separate feature flag or access control system. - [Cash Collection](https://getlago.com/platform/cash-collection): Payment orchestration with dunning, automatic retries, multi-gateway support, and payment links. - [Revenue Analytics](https://getlago.com/platform/revenue-analytics): MRR, gross revenue, invoiced usage, and usage trends across all revenue streams in a single dashboard. - [Lago Embedded](https://getlago.com/platform/embedded): White-label billing for platforms and marketplaces. Embed Lago's billing infrastructure under your own brand. - [Lago AI](https://getlago.com/platform/ai): AI-powered billing intelligence. Includes a finance assistant for querying billing data, a pricing assistant for scenario modelling, ML-based revenue forecasting, and an MCP server for connecting AI systems (Claude, ChatGPT) directly to Lago billing data and operations. - [Integrations](https://getlago.com/platform/integrations): Native integrations with Stripe, Adyen, GoCardless, Cashfree, NetSuite, Xero, Salesforce, HubSpot, Avalara, Anrok, AWS Marketplace, Azure Marketplace, GCP Marketplace, Segment, Hightouch, and more. ## Solutions by industry - [AI billing](https://getlago.com/solutions/industries/ai): Bill tokens, GPU compute, API calls, and credits. Supports hybrid models combining flat subscriptions with usage-based charges. Dynamic pricing for fluctuating model costs. Used by Mistral AI, Groq, Arcee, and others. - [Enterprise billing](https://getlago.com/solutions/industries/enterprise): Complex multi-entity billing with compliance controls, custom contracts, and enterprise plan management. - [Fintech billing](https://getlago.com/solutions/industries/finance): Accurate, compliant billing for fintech teams. Revenue recognition (ASC 606/IFRS 15) support, multi-currency, and audit trails. - [IoT & Telco billing](https://getlago.com/solutions/industries/iot): Device-level metering and complex usage billing for IoT platforms and telco/CPaaS providers. ## Solutions by use case - [Usage-based billing](https://getlago.com/solutions/use-cases/usage-based): Meter and bill any usage metric. Per-API-call, per-token, per-GB, per-seat, or any custom dimension. Real-time metering with full aggregation flexibility. - [Hybrid pricing plans](https://getlago.com/solutions/use-cases/hybrid-plans): Combine subscription base fees with usage-based overages, prepaid credits, and add-ons in a single billing system. - [Enterprise plans](https://getlago.com/solutions/use-cases/enterprise-plans): Custom pricing, committed minimums, negotiated terms, and multi-product billing in one contract. - [Multi-product billing](https://getlago.com/solutions/use-cases/multi-products): Bill multiple products across one or many customers in a unified billing system. - [Self-hosted billing](https://getlago.com/solutions/use-cases/self-hosted): Deploy Lago on your own infrastructure. Full codebase access, no vendor dependency, data sovereignty. AGPLv3 licensed. ## Solutions by team - [Engineering](https://getlago.com/solutions/teams/engineering): API-first billing infrastructure. Don't build billing from scratch. Every feature available via REST API. - [Product](https://getlago.com/solutions/teams/product): Ship pricing changes without engineering bottlenecks. Visual interface for creating and modifying plans. - [Finance](https://getlago.com/solutions/teams/finance): Automated invoicing, revenue recognition, and real-time reporting. Accurate billing data without manual reconciliation. - [Operations](https://getlago.com/solutions/teams/operations): All invoice and billing data in one place. Audit trails, webhook events, and integrations with accounting and CRM tools. ## Key blog posts and guides - [How to architect billing systems for usage-based pricing](https://getlago.com/blog/architect-billing-systems): Technical deep-dive for engineers building metering and billing infrastructure from scratch. - [The full playbook: How to design usage-based pricing models](https://getlago.com/blog/the-full-playbook-how-to-design-usage-based-pricing-models): Comprehensive guide to every usage-based pricing model — pure metered, hybrid, prepaid credits, outcome-based. - [6 steps to build a usage-based billing system](https://getlago.com/blog/6-steps-to-build-a-usage-based-billing-system): Step-by-step walkthrough building a hybrid billing system with the Lago API, replicating Segment's pricing model. - [Why billing is not just build or buy](https://getlago.com/blog/why-billing-is-not-just-build-or-buy): Why the billing decision is a long-term architecture commitment, not a make-or-buy calculation. - [Billing shouldn't suck](https://getlago.com/blog/billing-shouldnt-suck): Lago's founding thesis on why billing infrastructure has been broken and what a better model looks like. - [Why Stripe paid $1B for Metronome instead of fixing billing](https://getlago.com/blog/why-stripe-paid-1b-for-metronome-instead-of-fixing-billing): Analysis of the Stripe-Metronome acquisition and what it signals about the future of billing infrastructure. - [AI billing is (mostly) token plumbing](https://getlago.com/blog/ai-billing-is-mostly-token-plumbing): How AI companies should think about billing for tokens, compute, and credits. - [Entitlements and billing should be the same system](https://getlago.com/blog/lago-entitlements): Why feature access and billing logic belong in one place. - [How to deal with massive unpaid AI bills](https://getlago.com/blog/how-to-deal-with-massive-unpaid-ai-bills): Budget controls, spending limits, and alerting for AI products with variable cost exposure. - [Mistral billing: how Mistral handles subscriptions and usage for dozens of products](https://getlago.com/blog/mistral-billing): Customer story — how Mistral AI uses Lago for multi-product billing at scale. ## Documentation For full technical documentation, API reference, self-hosted setup guides, and integration tutorials, see the docs site: - [Documentation index](https://getlago.com/docs/welcome) - [API reference](https://getlago.com/docs/api-reference/intro) - [Full docs index for LLMs](https://getlago.com/docs/llms.txt) - [GitHub repository](https://github.com/getlago/lago) - [Community Slack](https://getlago.com/slack) - [Product changelog](https://getlago.com/docs/changelog/product)