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

# Advanced Features

Learn what features for advanced email sending scenarios Mailtrap Email API/SMTP provides.

Take your email sending to the next level with Mailtrap's advanced features. These tools are designed for power users who need more control over their email infrastructure and want to optimize their sending patterns.

## Features Overview

<table data-card-size="large" data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-target data-type="content-ref"></th></tr></thead><tbody><tr><td><strong>Custom Variables</strong></td><td><em>Add custom metadata to your emails for advanced tracking and segmentation. Pass through data that helps you analyze email performance in your own systems.</em></td><td><a href="/email-api-smtp/advanced/custom-variables.md">Custom Variables</a></td></tr><tr><td><strong>Excluding Links from Tracking</strong></td><td><em>Have sensitive links that shouldn't be tracked? Learn how to exclude specific URLs from click tracking while maintaining analytics for other links.</em></td><td><a href="/email-api-smtp/advanced/excluding-specific-links-from-tracking.md">Excluding Links from Tracking</a></td></tr><tr><td><strong>Auto BCC</strong></td><td><em>Automatically send blind carbon copies of all emails to a specified address for compliance and monitoring purposes.</em></td><td><a href="/email-api-smtp/advanced/auto-bcc.md">Auto BCC</a></td></tr><tr><td><strong>Webhooks</strong></td><td><em>Webhooks allow you to receive all information about your deliverability and activities within your account almost in real-time.</em></td><td><a href="/email-api-smtp/advanced/webhooks.md">Webhooks</a></td></tr></tbody></table>


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