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Where do I find my API key for each newsletter platform?

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Mike

Mike

Last updated on Nov 2, 2026

When you click + Add List and choose a platform, the app asks for that platform's key and, for most platforms, which list to track. Click How to get these credentials in the window to see these steps right where you need them.

Platforms move their menus around from time to time. If a menu name below doesn't match, look for "API" or "Developer" in your account settings.

Mailchimp

The app asks for your API Secret, then your Audience.

  1. Log in to Mailchimp and click your profile icon, then Account & billing.
  2. Go to the Extras tab and click API keys.
  3. Click Create A Key and copy it.
  4. Paste it into API Secret, click Find Audiences, and choose your audience.

Mailchimp keys end with a dash and a short code such as "-us21". Copy the whole key, including that ending.

Kit

The app asks for an API Key only. Kit tracks your whole account rather than one list.

  1. Log in to Kit and go to Account Settings, then Developer (app.kit.com/account_settings/developer_settings).
  2. Click Add a new key, give it a name, and copy it.

This is a v4 API key. There's no app authorization step.

MailerLite

The app asks for an API Token only. MailerLite tracks your whole account.

  1. Log in to MailerLite and go to Integrations.
  2. Choose MailerLite API.
  3. Click Generate new token, name it, and copy it.

Beehiiv

The app asks for an API Key and a Publication ID.

  1. Log in to Beehiiv and open Settings, then Integrations, then API, and create or copy your API key.
  2. Find your Publication ID in your publication settings, or in the address bar when you're viewing that publication. It starts with "pub_".

EmailOctopus

The app asks for an API Key, then your List.

  1. Log in to EmailOctopus and go to Account Settings, then API Keys (emailoctopus.com/developer/api-keys).
  2. Generate a new key and copy it.
  3. Paste it in, click Find Lists, and choose your list. You don't need to look up a list ID.

Sendy

Sendy is installed on your own server, so the app asks for an Installation URL, an API Key and a List ID.

  1. Installation URL: your Sendy address, for example https://send.yoursite.com. It must start with https:// and have no slash at the end.
  2. API Key: log in to your Sendy installation and go to Settings, then General.
  3. List ID: on Sendy's View all lists page, copy the encrypted ID shown next to the list.

Sendfox

The app asks for an Access Token, then your List.

  1. Log in to Sendfox and open Settings, then Connections, then API tokens (sendfox.com/account/oauth).
  2. Click Create New Token, name it, and copy it. Sendfox shows it only once.
  3. Paste it in, click Find Lists, and choose your list.

Sendfox's API is only available on paid Sendfox plans.

Flodesk

The app asks for an API Key, then your Segment. In Flodesk, a segment works as the list.

  1. Log in to Flodesk and open Account, then Integrations, then API keys (app.flodesk.com/account/integrations).
  2. Click Create API key, name it, and copy it.
  3. Paste it in, click Find Segments, and choose the segment.

Flodesk reports subscriber counts only, not open or click rates.

Brevo

The app asks for an API Key, then your List.

  1. Log in to Brevo and open the API keys page (app.brevo.com/settings/keys/api). It's under SMTP & API in your account or organisation settings.
  2. Click Generate a new API key and name it.
  3. Set Contacts to All and Email campaigns to Read. Leave everything else on None.
  4. Copy the key. Brevo shows it only once.
  5. Paste it in, click Find Lists, and choose your list.

After you paste the key

Click Connect List. The app checks the key with the platform before saving. If something is wrong you'll see the platform's error in red. See the troubleshooting article for what each message means.