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Select a subset of traffic using filters.

Speedscale provides the ability to filter traffic matching a pattern. Filters are used extensively by Speedscale during:

  • Traffic collection - to eliminate repetitive or sensitive information like heartbeats, monitoring requests or PII
  • Snapshot creation - to isolate a particular 3rd party service to mock or a test pattern
  • Assertions - to tailor which tests are run for specific traffic patterns

The simplest way to build a forwarder filter is to assemble it in Traffic Viewer. Editing the JSON is a lot more work but you can check out the instructions here


Filters are stored in Speedscale cloud so they can be reused. Manipulate them directly using speedctl commands like pull, edit, push and delete. To configure the Forwarder to use a filter rule insert the filter's ID in the Operator or Forwarder's SPEEDSCALE_FILTER_RULE environment variable.


Use the speedctl analyze filter command to test your filters against a snapshot to see which RRPairs will be filtered out. This command also works with a single RRPair downloaded from the UI.


Filters can be created in the Speedscale app but the UI does not provide access to the full expressiveness of the filters. If you're looking to do something advanced it's best to get as far as you can in the UI and then modify the JSON manually.