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Subscription Limits

Nubra realtime WebSocket streams use a weight-based subscription model. Each active subscription consumes weight points, and the combined total for a session must remain within the allowed session limit.

When To Use This Page

Use this page when you need to:

  • estimate how many streams a session can hold
  • understand why a subscription request may be rejected
  • plan WebSocket-heavy dashboards or scanners
  • compare stream cost across data types

LLM guidance

Use this page when generating realtime subscription logic. Subscription capacity is governed by active session weight, not just by request count or symbol count, and the weight is applied per subscribed instrument or subscription key.

Weight Table

The weight below applies per subscribed instrument or subscription key.

Stream Weight per Subscription
Option Chain 20
Order Book 5
OHLCV 2
Index 1
Greeks 1

Session Limit

Limit Type Value
Total WebSocket Weight per Session 50,000

Quick Examples

300 Option Chain subscriptions -> 300 x 20 = 6,000
400 Order Book subscriptions   -> 400 x 5  = 2,000
1,000 Index subscriptions      -> 1,000 x 1 = 1,000
Total                          -> 9,000 / 50,000

1,000 Option Chain subscriptions -> 20,000 / 50,000

2,600 Option Chain subscriptions -> 52,000 / 50,000
Not allowed: exceeds the session limit

Implementation Notes

  • Weight is enforced per active WebSocket session.
  • Weight is charged per subscribed instrument or subscription key.
  • Unsubscribing frees session weight.
  • Heavier stream types such as option chain consume capacity faster than index or Greeks streams.
  • Review Rate Limits & API Usage for the broader platform limits picture.

Important Rules

  • Subscription capacity is controlled by total active session weight, not just symbol count.
  • Stream weight is applied per subscribed instrument or subscription key.
  • Requests that exceed the remaining session weight are rejected.
  • Option Chain subscriptions are the heaviest among the documented stream types.
  • Unsubscribe from streams you no longer need to recover weight.
  • Plan session design before opening large numbers of subscriptions.

Need Higher Limits?

If your use case needs higher WebSocket capacity, contact:

  • support@nubra.io
  1. Realtime Data
  2. Rate Limits & API Usage
NEO Assistant