Data Extension Limits and Guidelines

The size, structure, and number of data extensions and contact attributes data can impact their performance. To optimize the performance of your data extensions and contact attributes, stay within recommended ranges.

Guidelines by Entity Type

For each data element, this table shows an approximate range for each of these performance categories.

These values are guidelines for best performance, not hard limits. If your account falls into the Aggressive or Extreme categories for one or more entity types but you don’t experience any performance issues, then you aren’t required to make any changes.

  • Efficient: The optimum range for time-sensitive imports and high performance.
  • Typical: High performance for general use.
  • Aggressive: Values in this range can impact performance.
  • Extreme: Values in this range are likely to degrade performance.
Entity Efficient Typical Aggressive Extreme
Number of sendable data extensions Fewer than 1,000 1,000–4,999 5,000–9,999 10,000 or more
Number of columns, fields, or attributes Fewer than 30 30–75 76–150 151 or more
Number of fields with high character limits 0 1–2 3–4 5 or more
Number of rows Fewer than 10 million 10 million–100 million 100 million–1 billion More than 1 billion

If your account experiences performance issues, consider these solutions:

  • Delete unused data extension or contact attribute fields.
  • Split up fields across several data extensions, rather than creating one large data extension. Then, connect multiple related data extensions in Contact Builder or Email Studio.
  • Delete older data from data extensions. For example, implement a data retention policy to delete rows when they reach a certain age. You can also use SOAP API to delete specific rows.
  • Reduce the number of text fields that have a high character limit. To implement this solution, add a column to the data extension with a smaller character limit. Next, use a query to move data from the older column to the newer one. Finally, delete the older column.
  • Move the data from large data extensions into an archive. To implement this solution, click the Clear Records button in the data extension to move the data to the Recycle Bin. Next, from the Recycle Bin, click Restore to move the cleared data to a new data extension. The new data extension acts as an archive. Delete the archived data extension when you no longer need the data. See Manage Data Extension Records.
  • Mark any data extensions that are no longer used for sending email messages as not sendable. See Manage Data Extensions.
  • For data extensions that aren't needed, you can modify their data retention policy to delete them when the retention period expires. See Enable and Modify Data Extension Retention Policies.