> For the complete documentation index, see [llms.txt](https://docs.encharge.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.encharge.io/transactional-email-api/authentication.md).

# Authentication

Authenticate by passing an API key in the `token` query parameter or the `X-Encharge-Token` header. Get your API key from [your Account](https://app.encharge.io/account/info).

Continue to the [API Reference](https://docs.encharge.io/transactional-email-api/reference).