> For the complete documentation index, see [llms.txt](https://documentation.alpaco.email/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://documentation.alpaco.email/how-to/subject-line-and-preheader.md). # Subject line & Preheader Arguably one of the most important aspects of email marketing is writing a banger of a subject line and preheader to grab readers attention to even open your email in the first place. ### Editor In the editor users are able to insert both Subject line and preheader for their email. The editor will give indications if the suggested amount of characters have been reached.\ More advanced ESP's are able to pick up one or both of these fields at export, saving you time to have to do it again.

### How to insert Subject line & Preheader into HTML For some ESP's it's not part of their export options and thus it needs to be either manually inserted when sending out the email, and some of the fetch the information straight from the HTML. In these cases we've made it possible to insert those fields from the editor, so you don't have to create your own.\ \ **Subject line** ```html {{subjectline}} ``` **Preheader** {% code overflow="wrap" %} ```html ``` {% endcode %} --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://documentation.alpaco.email/how-to/subject-line-and-preheader.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.