Horizon API vs RPC vs Indexers: Deep Comparison for Stellar Developers
Choose the right data access architecture for your Stellar application.
Choosing between Horizon API vs RPC is one of the first architectural decisions Stellar developers face. Add custom indexers to the mix, and the options multiply. This guide compares all three approaches, helps you find the best Stellar API providers, and provides concrete recommendations based on your use case. Whether you need a Stellar blockchain data API for real-time trading, historical analytics, or smart contract monitoring, this comparison will help you choose the right approach.
The Three Approaches to Stellar Blockchain Data
The Stellar ecosystem provides three primary ways to access blockchain data. Understanding the tradeoffs between Horizon API vs RPC and custom indexers is critical for building performant applications.
| Feature | Horizon API | Stellar RPC | Custom Indexer |
|---|---|---|---|
| Data Type | Historical + indexed | Real-time state | Custom aggregations |
| Protocol | REST + SSE | JSON-RPC 2.0 | Custom (SQL, GraphQL) |
| Latency | ~100-500ms | ~50-200ms | ~10-100ms |
| Smart Contracts | Limited | Full support | Custom |
| Ops Burden | Low (managed) | Low (managed) | High (self-managed) |
| Tx Simulation | No | Yes | No |
| Cost | Free-$99/mo | Free-$99/mo | $200-2000+/mo |
Horizon API: The Stellar Blockchain Data API Standard
Horizon is the original Stellar blockchain data API. It ingests every ledger, indexes it in PostgreSQL, and exposes a RESTful interface. You can explore it through our API documentation.
Best for: Account balances, transaction history, payment streams, offer book queries, asset metadata, and building blockchain explorers.
Our Stellar Network Analytics Dashboard and Natural Language Query Interface both use Horizon as their primary data source for historical queries.
Stellar RPC: Real-Time State and Smart Contracts
The Stellar RPC API service is optimized for real-time operations. Read our complete Stellar RPC guide for the full method reference.
Best for: Transaction simulation, smart contract storage, event queries, fee estimation, and real-time state. Essential for any app using Soroban smart contracts.
Custom Indexers: When You Need More
Custom indexers ingest raw Stellar data and store it in your own database with custom schemas. They're powerful but require significant infrastructure investment, including Stellar node monitoring tools to ensure your ingestion pipeline stays healthy.
Best for: Complex analytics, custom aggregations, cross-entity queries, and applications requiring sub-10ms latency. See our guide on monitoring Stellar nodes in production if you go this route.
Finding the Best Stellar API Providers
When evaluating the best Stellar API providers, consider these factors:
Reliability & Uptime
Look for providers with SLA guarantees and redundant infrastructure. LumenQuery provides 99.9% uptime with automatic failover.
Dual API Support
The best Stellar API providers offer both Horizon and RPC through a single account. LumenQuery provides both at transparent pricing.
Developer Experience
Good documentation, SDKs, and support make a difference. Check our API docs and 2026 provider comparison.
Monitoring & Observability
Providers should offer usage dashboards and Stellar node monitoring tools integration. See our analytics documentation.
Decision Framework: Which Approach to Use
Building a payment app?
Use Horizon API for account lookups, path finding, and payment history. Add Stellar RPC only for transaction simulation.
Building a DeFi protocol?
Use Stellar RPC as your primary interface for contract interactions, simulation, and events. Use Horizon for trade history.
Building analytics?
Start with Horizon API (like our analytics dashboard). Graduate to a custom indexer when you need complex aggregations.
Building a portfolio tracker?
Use both APIs together. Horizon for balances and history, RPC for DeFi positions. See our Portfolio Intelligence docs.