MailerLite Launches Simple Email Editor and Custom HTML Builder With AI Agent.

MailerLite has released two new email editors designed to address different workflows in email campaign creation. The update, announced on LinkedIn, introduces a distraction-free Simple email editor for writers and a Custom HTML builder with an integrated AI agent for developers.

The company's existing drag-and-drop editor remains available, giving users three distinct paths for building campaigns depending on their technical requirements and design preferences.

The Simple email editor strips away visual design elements to focus on writing. According to MailerLite, the editor preserves formatting during copy-paste operations, addressing a common frustration where rich text loses structure when moved between applications.

The interface removes layout grids, image placement tools, and styling panels that characterize visual email builders. Users work in a linear text environment similar to a word processor, then apply basic formatting options like bold, italics, and hyperlinks.

This approach mirrors a broader trend toward simplified creation tools. Substack and Beehiv have built audiences around straightforward writing interfaces that prioritize content over design complexity. MailerLite's move suggests demand for this workflow extends beyond newsletter platforms into broader email marketing tools.

The Custom HTML builder targets users who need granular control over campaign code but lack deep development expertise. The editor includes an integrated AI agent that generates and modifies HTML through natural language prompts.

Users can describe desired changes in plain language rather than writing code directly. The AI agent interprets requests and outputs corresponding HTML, which appears in a side-by-side code view for inspection and manual adjustment if needed.

MailerLite positions this as eliminating context switching between email builders and external AI tools like ChatGPT or Claude. The company has been expanding AI integrations across its platform, having recently enabled third-party AI connections and launched an MCP server for direct data access.

The HTML editor also supports ZIP imports from Canva up to 10MB, up from previous file size limits. Users can export designs from Canva as HTML packages and upload them directly into campaigns.

MailerLite now offers three campaign creation paths:

• Drag-and-drop editor: Visual block-based builder for users who want design control without code
• Simple editor: Text-focused environment for copy-first workflows
• Custom HTML + AI: Code-level control with natural language assistance

The tiered approach reflects how email marketing tools are segmenting to serve increasingly specialized workflows. Mailchimp and ConvertKit have similarly expanded their editor options as user bases have diversified beyond traditional marketing teams to include solopreneurs, content creators, and technical users building transactional email systems.

Both new editors are available in the MailerLite dashboard at no additional cost. The company has published a detailed walkthrough on its blog covering setup and feature details for each editor.