> For the complete documentation index, see [llms.txt](https://developers.cryptopay.me/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developers.cryptopay.me/guides/invoices/payment-widget.md).
# Online checkout
Merchants do not always need custom API integration. In order to accept payments, Merchant can save time and integrate our [online checkout](https://demo-business-sandbox.cryptopay.me/).
An online checkout is a ready-made tool based on [invoices](https://developers.cryptopay.me/guides/invoices), that you can plug into your website and start accepting cryptocurrency payments without integrating the API.
The checkout is designed both for desktop and mobile web browsers. It can be used as a pop-up or embedded part of your website.
Check this demo [https://demo-business-sandbox.cryptopay.me](https://demo-business-sandbox.cryptopay.me/) to see what it looks like.
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