Learn what triggers API activity and how it affects your limits.
Marketo has a default limit of 50,000 API calls per day. To help you stay within that limit, this guide explains when Optimize makes API calls to sync data, personalize sessions, and keep your dashboard up to date.
Pro tip
If you're concerned about hitting your daily API call limit, you can contact us to cap daily API calls or throttle usage by limiting the percentage of visitors eligible for Marketo-based personalization.
Association calls during live sessions
When a visitor arrives on your site with a Marketo cookie, Optimize tries to associate them with their Marketo data in real time. This allows Optimize to personalize the visitor's current session — instead of waiting for the next scheduled data sync.
The number of association calls made each day depends on how many visitors arrive with an active Marketo cookie.
Daily sync and export limits
Optimize performs a daily incremental sync to fetch updated data for your imported Marketo fields and lists. These API calls are minimal and typically won’t affect your daily API quota.
Marketo also imposes a daily export allocation limit of 500MB. While Optimize’s incremental syncs reduce data volume, syncing large datasets may still trigger this limit. For example, exporting two 250MB files in one day would hit the 500MB export cap.
API calls from the dashboard
Each time the Marketo import settings load — whether you're viewing imported smart lists or fields — API calls are made to refresh your synced data. This happens automatically when opening the page, refreshing it, or accessing it in a new browser tab, and applies to any user who views the page.