If you want to set up an integration with your MailChimp account, chances are high that you'll need to generate an API key. Users with Manager permissions can generate and view their own API keys. Users with Admin permissions can also see API keys for other account users.
- Click on this link https://login.mailchimp.com to navigate to the API Keys section of your MailChimp account
- Click your profile name to expand the Account Panel and choose Account Settings.
- Click the Extras menu and choose API keys
- Copy an existing API key or click the Create A Key button.
- Name your key descriptively, so you know what application uses that key.