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Find the Number of API calls required for your Salesforce integration

How many API calls are needed for a new Audience of 25,000 subscribers in Mailchimp? 

Let's take a look at an example like Mailchimp for Salesforce integration and the API usage needed.

SyncApps will do the following process to sync Mailchimp for Salesforce in this use case:

  1. Look in the Salesforce email cache to see if the record exists, and if so, then do not process;
  2. Look in Salesforce as to whether the email address exists, and if so, then do not process;
  3. If the email address does not exist in Salesforce, then create a new record in Salesforce.

If there are no cached data in SyncApps for most of the email addresses syncing back to CRM, then SyncApps will process 25,000 requests to Salesforce to check whether the email address exists.

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A few options to avoid any Salesforce API overage and still capture Marketing Metrics efficiently:

  1. Turn off the feature in Step 1 called the "Sync Campaigns" feature, then do initial sync so all email addresses from CRM will be cached by SyncApps.
  2. The "Sync All Campaign Members" feature in Step 2 should be enabled to cache new records into SyncApps to capture all initial Campaign Responses into Salesforce.
  3. Turn off the feature in Step 1 called "Use CRM checkbox field(s) for List segmentation".
  4. Alternatively, if you don't want new Contacts to be created in Salesforce from Mailchimp, please disable two-way syncing in Step 2 using our One-Way feature. Campaign Response, or Marketing Metrics as they are commonly called, will still be synced if you enable this option.
  5. Only Campaign Metrics for Contacts that have been previously synced from Salesforce to Mailchimp will be populated so if you have only a few records synced initially from Mailchimp previously, then only these will be populated with Campaign Response Metrics unless the "Sync All Campaign Members" feature in Step 2 is turned on.

So in this use case, the first option is best practice:

  1. Starting with an empty Mailchimp Audience and populating the Audience with Contacts and/or Leads from Salesforce is the best practice to minimize API usage.


Estimate API Calls for Campaign Response (Marketing Metrics) feature:

  • SyncApps needs fewer API calls if using an Empty Mailchimp Audience.
  • Each API call can update 200 Salesforce records, so for 10,000 Campaign Responses, only 50 calls will be needed.
  • Retrieving Contacts and Leads from Salesforce also requires far fewer API calls.

Currently, SyncApps uses 500 records per call, so 20,000 records will only need 40 API calls.

API Calls needed when an email address is not in the cache would be like this, 20,000 records in Mailchimp, there will be 20,000 calls required if you do not sync first all your Contacts and Leads.

If you sync all Contacts, there will be no problem as on initial sync SyncApps will retrieve Salesforce contacts and put them in SyncApps Cache, making retrieving all Marketing Metrics on subsequent syncs super simple.

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    If you are migrating large numbers of records (10k, 20k, 50k, 100k, 1,000,000+) from MailChimp, Constant Contact, VerticalResponse or other Marketing Automation systems to Salesforce we have a SyncApps customizatoin we can turn on which will cache existing records from Salesforce to minimize API calls.

    *Only 100 API calls required to cache 50K emails in Salesforce.

    Please reach out to our ASK team ( today to have it turned on in your account.