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

# Useful Links

Quick links to the pages and tools you will use most while building on the Etherscan API.

## Account and keys

* [Register](https://etherscan.io/register): create a free Etherscan account.
* [API dashboard](https://etherscan.io/myapikey): create and manage your API keys.
* [API plans and pricing](https://etherscan.io/apis): compare tiers and upgrade.

## Documentation

* [Set up your API key](/set-up-your-api-key): create an account and make your first request.
* [Make your first call](/make-your-first-call): make your first useful call and read the response.
* [API reference](/api-reference/endpoint/balance): every endpoint, grouped by resource.
* [Supported chains](/supported-chains): all chains and their `chainid` values.
* [Rate limits](/rate-limits): the calls-per-second and daily limits for each plan.
* [Common error messages](/common-error-messages): what each error means and how to fix it.
* [Changelog](/changelog): product updates and endpoint changes.

## Support

* [Contact us](/resources/contact-us): reach the team for help.
* [PRO endpoints](/endpoint-overview): what paid plans add.

## Explore

* [etherscan.io](https://etherscan.io): the block explorer.
* [Etherscan on X](https://x.com/etherscan): product updates and announcements.