This is a guided walkthrough of integrating with the Mailchimp Transactional API (formerly Mandrill) in PHP. Each step below is a standalone page that performs one API call, shows the code that did it, and prints the raw request & response.
config.php and paste it in, or follow the
setup guide for how to generate one.
How to enable Transactional email on your Mailchimp account and generate a key.
1Hits /users/ping. Always do this first — if auth is broken, nothing else will work.
2Hits /allowlists/list. Shows which emails are currently allowlisted (exempt from rejection).
3Hits /allowlists/add — the endpoint from the docs page you shared.
4Hits /allowlists/delete. Completes the CRUD cycle so you can clean up.
5Hits /messages/send. The core of the API — what you'll actually use in production.
6Hits /templates/list. Templates let you design emails once and reuse them with merge vars.
7Hits /templates/add, then shows how to send using it with /messages/send-template.
8Hits /users/info and /tags/all-time-series to show sending reputation and recent activity.
The demo is deliberately flat — no framework, no Composer. Just PHP files you can read top-to-bottom:
| File | What it does |
|---|---|
config.php | Holds your API key and the default sender identity. |
lib.php | One function — mandrill_call() — that every page uses. Wraps cURL and returns a structured result. |
header.php / footer.php | Shared HTML shell and navigation. |
style.css | Styling. No dependencies. |
01-... – 08-... | One page per API call. |
Every page renders a "What just happened?" panel showing the exact JSON that was sent and received (with the API key redacted) so you can learn the shape of each endpoint by doing.