1. Open the Mailchimp API keys page
Log in if asked. You'll land on the API keys screen with a list of any keys already on the account.
Free plan works. You can create an API key on any Mailchimp plan, including free. Your sending limits still apply, the key just lets a tool talk to your account.
2. Create a new key
- Click Create A Key
- Give it a name like Zapier or Stein Solutions integration so you know what it's for later
- Mailchimp shows you the key, starting with a long random string and ending with a dash and a code like
-us21
Copy the whole thing, including the part after the dash. Both halves matter.
Persistent. You can come back to this page and copy the key again later. Unlike some tools, Mailchimp does not hide it after the first reveal.
3. Note your datacenter
The bit after the last dash in your key is your datacenter. For example, if your key ends in -us21, your datacenter is us21.
Most tools ask for the key alone. A few (especially custom integrations) ask for the datacenter separately so they can build the API URL. If a tool asks for "Mailchimp datacenter" or "Mailchimp server prefix," that's where to look.
Heads up on free plan limits. Your key has full access to the account, but Mailchimp's free plan caps you at 250 contacts and 500 sends per month. If your automation hits that wall, the key isn't the problem, the plan is.
Working with Jeanette?
Stop here. Jeanette will take care of the rest. Just copy the key and send it to her directly. She'll handle the integration setup, whatever tool it's connecting to.
Not sure how to send it? Book a quick call →
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