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Order Entry Limits

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FIX 4.2

The FIX 4.2 Order Entry API rate limits are:

  • 50 requests per rolling second1 per session
  • 100 messages per second in bursts

Rolling second

The clock starts when the first command is sent. We use a lazy-fill token bucket implementation.

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FIX 5

The FIX 5 Order Entry API rate limits are:

  • 2 logons per second per API key
  • 100 requests per second

Your FIX 5 session is disconnected if your messages exceed 200 messages per second

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Maximums

  • Maximum connections per profile: 75. See FIX Best Practices.
  • Maximum connections per user across all profiles: 175
  • Maximum API keys per session/connection: 1
  • Maximum profiles per user: 100
  • Maximum orders per batch message (new and cancelled): 15

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Market Data Limits

The FIX Market Data API is limited to 1 connection per API key. It does not use FIX order entry rate limits (connections, rps, burst rps).