> For the complete documentation index, see [llms.txt](https://usd1.gitbook.io/whitepaper/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://usd1.gitbook.io/whitepaper/master.md).

# Welcome to USD1

USD1 is the safest US dollar [stablecoin](https://en.wikipedia.org/wiki/Stablecoin) bridging the crypto and fiat worlds.

Every single USD1 ERC-20 token in existence is backed by an actual US dollar held in a fund under custody by a tier 1 global bank. This fund is administered by an independent, fully-licensed administrator, audited by a "big four" accounting firm, and reviewed regularly for strict adherence to Know Your Customer / Anti Money Laundering (KYC/AML) procedures by a fully-licensed law firm, all operating under the robust financial regulatory framework of the Hong Kong SAR.

The is no other stablecoin in existence that offers this level of institutional-grade security.