EPAM B2BITS FIX Client Simulator allows initiating and accepting FIX sessions, exchanging and editing FIX messages. The tool is based on .NET technologies and can be used to simulate FIX buy and/or sell side end points. Built on top of the FIX Antenna® engine FIX Client Simulator shares all its common features and benefits. The tool also uses B2BITS' FIXopaedia as a FIX reference source and provides complete support of all standard and custom FIX dictionaries.


  • Establish multiple acceptor/initiator sessions to local and/or remote hosts
  • Save session configuration and restore sessions from the list after disconnecting
  • Override Sender and Target CompIDs for established session
  • Definition or reset of manual sequence numbers ('in' and/or 'out')
  • Restart of working session
  • Events monitoring:
    • sent and received messages
    • active sessions
    • sessions statuses in real-time
  • Write, open, and edit raw FIX messages in a table 
  • Search for acharacter or character sequence in a raw FIX message
  • Load, modify and send a file containing a preset message or a batch of messages
  • Send messages in a defined interval
  • Optional message validation for both incoming and outgoing messages (i.e. wellformness, required and conditionally required fields, fields order, types, etc.)
  • Enable/disable message resending
  • Option to use SSL protocols
  • Supports:
  • Unregistered acceptor sessions
  • Standard FIX versions 4.0 - 5.0 SP2 and dialects (extra field(s) for the standard FIX message(s), custom tags values, user-defined tags and messages) via friendly XML
  • All FIX message types (pre-trade, trade, post-trade, market data, etc.)
  • Wide range of FIX session settings including Custom Logon messages

FIX Client Simulator is provided as a simple zip archive. The package contains messages samples and an example of a custom dictionary.

A short introduction video to FIX tools, including the FIX Client Simulator, can be found here.

Please contact us at sales@b2bits.com to obtain the free trial version of FIX Client Simulator or for any additional information.