Limitations on Historic Data Submission to Mixpanel

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Mixpanel allows you to import historical data without a strict technical limit on the time period—using the Import API, you can ingest events with timestamps as far back as January 1, 1971. There is no hard cap on the amount of historical data you can send, but best practices and recommendations are provided: - Recommended Time Window: Mixpanel generally recommends backfilling up to one year of historical data, or up to two years in some migration scenarios, to balance usefulness and manageability. Importing more than this is possible, but may introduce complexity and higher billing costs. For most migrations, loading a year’s worth (or less) of historical data is advised, especially when migrating from platforms like Adobe Analytics or Google Analytics. If you need to retain more, consider storing older data in a data warehouse instead of Mixpanel itself Loading historical data Backfilling Historical Data Undertaking discovery: Why and what is historical data for. - Technical Limits: The Import API supports ingesting billions of events per day, with a rate limit of 2GB of uncompressed JSON per minute or about 30,000 events per second. Each request can include up to 2,000 events Rate Limits Track Events. - SDK/Client-Side Limits: If you use Mixpanel’s client-side SDKs (e.g., for iOS, Android, Unity, Flutter), you can only send events with timestamps within the last 5 days. For older data, you must use the Import API Mixpanel SDKs: Android Mixpanel SDKs: iOS Mixpanel SDKs: Unity Mixpanel SDKs: Flutter.Summary: You can technically import as much historical data as you want (even several years’ worth), but Mixpanel recommends limiting this to one or two years for practical and billing reasons. For events older than 5 days, always use the Import API. If you need to import more than the recommended amount, be aware of potential billing impacts and data model differences between systems.

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Your project's data older than 5 years was removed due to Mixpanel's data retention policy. By default, Mixpanel automatically deletes events after 5 years from the event date. This retention period applies to all projects created before September 1, 2025. For projects created after that date, or if you modify your plan or move to the Free Plan, the retention period is reduced to 2 years. The retention period starts from the date the event occurred (the "Event Date"), not the date it was ingested by Mixpanel GDPR Compliance: Data Retention Policy.If your project was created before September 1, 2025 and you have not changed your plan, the 5-year retention applies. Otherwise, the retention may be shorter. This automatic deletion is part of Mixpanel’s standard data privacy and management practices.

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