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

# Overview

The SQL API is a zero-infrastructure indexing solution that allows any developer to pull real-time and historical onchain data on Base and Solana using custom SQL queries. SQL API gives you complete flexibility to query any blockchain data.

<Card title="Try it now: Quickstart" icon="rocket" href="/data/sql-api/quickstart">
  Run your first query in the SQL Playground—no API keys required
</Card>

Developers can access the SQL API through:

<CardGroup cols={2}>
  <Card title="SQL Playground" icon="browser" href="https://portal.cdp.coinbase.com/onchain-tools/sql-api">
    Try queries in your browser (no API keys needed)
  </Card>

  <Card title="REST API" icon="code" href="/data/sql-api/rest-apis">
    Programmatic access with free API keys
  </Card>
</CardGroup>

## Key Features

* **Zero Infra:** No setup, no guesswork. Just real-time indexed onchain data.
* **Customizable:** Leverage familiar SQL syntax to pull custom data.
* **Responsive:** Pull custom onchain data with \< 500ms latency.
* **Fresh:** \< 250ms end-to-end from tip of chain.

## Use Cases

* **B20 issuers and apps:** Query [B20 native token events](/data/sql-api/b20-events)—transfers, memos, mints, policy updates, and factory deployments—on Base Mainnet and Base Sepolia.
* **Solana token activity:** Track [SPL Token and Token-2022](/data/sql-api/solana-tokens) transfers and instruction-level activity for a mint, wallet, or program on Solana Mainnet.
* **Builder Code attribution:** Measure the onchain activity attributed to your app with [Builder Code queries](/data/sql-api/builder-codes)—EOA transactions and ERC-4337 user operations tied to your code.
* **Payment Service Providers:** Track real-time stablecoin transactions for merchants, consumers, and marketplaces.
* **Portfolio & Treasury:** Give users and institutions a live view of wallet balances and historical flows. Build dashboards that update instantly as funds move across chains, protocols, and counterparties.
* **Onchain Games:** Track player inventory, asset upgrades, and progression in real time as NFT metadata evolves. Enable game mechanics that reflect actual onchain state — not stale snapshots.
* **Onchain Social:** Monitor user interactions like tips, follows, and reactions across decentralized social graphs. Surface meaningful engagement and value transfer between users, apps, and agents.

## Schema

The SQL API runs queries against an opinionated schema for efficient organization and response delivery. You can read more in the [schema reference](/data/sql-api/schema). For the CoinbaSeQL grammar, you can find that in the [CoinbaSeQL reference](/data/sql-api/sql).

## Pricing & Rate Limits

SQL API operates on a pay-as-you-go model:

* **1,000 free queries every month**
* **After the free tier:** \$0.0083 per query
* **Rate limit:** 2 queries every second per project (default)

## Support and feedback

Join **#onchain-data** in the [CDP Discord](https://discord.com/invite/cdp) to access FAQs, schedule project discussions, and connect with other developers. We welcome your feedback and suggestions for improvement.