# Mailchimp Developer
# Build with Mailchimp
Mailchimp’s developer tools provide everything you need to integrate your data with intelligent marketing tools and event-driven transactional email and SMS.
Mailchimp Marketing API
[Send marketing campaigns](/developer/marketing)
* [Mailchimp core concepts](/developer/marketing/concepts)
* [API core concepts](/developer/marketing/api-concepts)
* [Building with Mailchimp](/developer/marketing/build)
* [API Reference](/developer/marketing/api)
Mailchimp’s Marketing API powers timely, relevant marketing campaigns with custom data pulled directly from your app.
Mailchimp Transactional
[Send transactional email and SMS](/developer/transactional)
* [Quick Start](/developer/transactional/guides/quick-start)
* [API Reference](/developer/transactional/api)
* [Documentation](/developer/transactional/docs/fundamentals)
Mailchimp Transactional (formerly Mandrill) sends targeted and event-driven messages via the API or SMTP, fast—with best-in-class deliverability.
## You’ll be in good company
When you build integrations with Mailchimp, you’re creating tools for a trusted and reliable platform that powers marketing, e-commerce, and more for millions of small businesses.
14M
Trusted by fourteen million customers and counting
1B
Rock-solid reliability delivers 1 billion emails daily
300+
Dev teams have launched over 300 Mailchimp integrations so far
Mailchimp Integration Partner Program
## A helping hand to scale your Mailchimp Integration
As an Integration Partner, you’ll have access to exclusive benefits, insights, and opportunities to grow your business.
[Learn more](/developer/integration-partner-program)
## \$1 Million to the Developer Community
We’ve invested in the developer community with a fund to power the creation of new Mailchimp integrations. Keep an eye on the integrations directory to see what’s new!
[Browse Integrations](https://mailchimp.com/integrations/)
> On the Mailchimp side, the fact that the API allows us to send automated emails to catch potential customers that might otherwise be lost is a great feature.
Santiago Paragarino, Senior Magento developer & Gonzalo Dominguez, Senior Engineer, Ebizmarts
> Developing the integration using the Mailchimp API 3.0 was a good experience, documentation is easy to understand and very detailed with proper examples of all requests/responses.
Danilo Alvarenga, CTO, 3dcart
> We use the Mailchimp API to simplify our onboarding. We were able to cut down our onboarding by 80% because now a user can just sign in and start listening to music and then we can relate back the music you listen to to your profile.
Patrick Hill, Executive Director, Disctopia
> Find all the Mailchimp API documentation and tools developers need to send marketing and transactional emails.
## Instructions for AI Agents
- For clean Markdown of any page, append `.md` to the page URL
- For section-specific indexes, append `/llms.txt` to any section URL
- For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://mailchimp.com/developer/_mcp/server
## Products
- [Mailchimp Marketing API](https://mailchimp.com/developer/marketing/llms.txt): Power timely, relevant marketing campaigns with custom data pulled directly from your app.
- [Overview](https://mailchimp.com/developer/marketing.md)
- [How Mailchimp works](https://mailchimp.com/developer/marketing/concepts/how-mailchimp-works.md)
- [Contacts](https://mailchimp.com/developer/marketing/concepts/audiences/contacts.md)
- [Merge fields](https://mailchimp.com/developer/marketing/concepts/audiences/merge-fields.md)
- [Segments](https://mailchimp.com/developer/marketing/concepts/audiences/segments.md)
- [Mailchimp Transactional](https://mailchimp.com/developer/transactional/llms.txt): Send targeted and event-driven messages to anyone, fast—with best-in-class deliverability.
- [Overview](https://mailchimp.com/developer/transactional.md)
- [Transactional API Quick Start](https://mailchimp.com/developer/transactional/guides/quick-start.md)
- [Send Your First Transactional Email](https://mailchimp.com/developer/transactional/guides/send-first-email.md)
- [Send Your First Transactional SMS](https://mailchimp.com/developer/transactional/guides/send-first-sms.md)
- [Change Sending Behavior with the Rules Engine](https://mailchimp.com/developer/transactional/guides/change-behavior-rules-engine.md)
- [Tools](https://mailchimp.com/developer/tools/llms.txt): Official client libraries and mobile SDKs for the Mailchimp APIs.
- [Tools - SDKs](https://mailchimp.com/developer/tools.md)
- [Release Notes](https://mailchimp.com/developer/release-notes/llms.txt): The latest updates, improvements, and fixes across the Mailchimp APIs.
- [August 19, 2025](https://mailchimp.com/developer/release-notes/2025/8/19.md)
- [August 7, 2025](https://mailchimp.com/developer/release-notes/2025/8/7.md)
- [December 6, 2024](https://mailchimp.com/developer/release-notes/2024/12/6.md)
- [June 17, 2024](https://mailchimp.com/developer/release-notes/2024/6/17.md)
- [February 12, 2024](https://mailchimp.com/developer/release-notes/2024/2/12.md)
- [Blog](https://mailchimp.com/developer/blog/llms.txt): Engineering stories and updates from the Mailchimp developer team.
- [June 10, 2025](https://mailchimp.com/developer/blog/reintroducing-mailchimp-transactional-for-your-email-and-sms-needs.md)
- [March 15, 2022](https://mailchimp.com/developer/blog/mailchimp-and-wordpress.md)
- [November 16, 2021](https://mailchimp.com/developer/blog/leading-teams-closing-loops.md)
- [August 17, 2021](https://mailchimp.com/developer/blog/breaking-down-remote-collaboration-conundrum.md)
- [May 11, 2021](https://mailchimp.com/developer/blog/changing-the-tires-on-a-moving-bus.md)
- [Integration Partner Program](https://mailchimp.com/developer/integration-partner-program/llms.txt): Grow your Mailchimp integration with exclusive partner benefits.
- [Integration Partner Program](https://mailchimp.com/developer/integration-partner-program.md)