> For the complete documentation index, see [llms.txt](https://bound-1.gitbook.io/bound-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://bound-1.gitbook.io/bound-docs/bound-auth/what-is-bound-auth.md).

# What is Bound Auth

Bound Auth is a passkey-based authentication system that creates self-custodial wallets across BTC, EVM, and Solana, with built-in backup and recovery.

## Why it matters

Traditional crypto onboarding often requires users to install browser extensions, manage private keys manually, and understand wallet recovery before they can get started. This creates significant friction and security risk.

Bound Auth eliminates this entirely. You sign up like any normal app - but you always maintain full self-custody of your assets. Your keys never leave your device.

## Key properties

* **No browser extensions** - works natively in your browser or app
* **Self-custodial** - you always control your own keys
* **Multi-chain** - one login creates wallets across BTC, EVM, and Solana
* **Works across all Bound products** - all features require Bound Auth

{% hint style="success" %}
Bound Auth eliminates the biggest friction point in crypto onboarding - without compromising on self-custody.
{% endhint %}