Introduction
Version: 0.10.7 • Status: Production • Public URL: wss://ws.gemini.com
Our WebSocket API provides low latency access to real-time market data and order execution for professional traders and institutions. Built from the ground up for performance, our WebSocket API delivers fastest latency on AWS with enterprise-grade reliability.
Key Features
- Low Latency - Sub-10ms market data updates for competitive advantage
- Real-Time Trading - Place and cancel orders via WebSocket
- Multiple Streams - Subscribe to multiple markets simultaneously
Performance Tiers
| Tier | Target | Description |
|---|---|---|
| Tier 2 (Public Internet) | p99~15ms | Public offering connecting to AWS us-east-1 over the public internet. Provides good baseline performance with minimal setup complexity. |
| Tier 1 (In Region) | p99~10ms | Direct connection to us-east-1 feed. Provides improved performance a step above the public offering but requires onboarding to peer to our infrastructure. |
| Tier 0 (Local Zone) | p99~5ms | Best performance outside of NY5, physically closest to our data center. Requires onboarding similar to us-east-1. |
Please email api@gemini.com to onboard to our WebSocket high performance tiers.
Connection Parameters
Connection-level query parameters can be passed in the WebSocket URL to customize behavior:
| Parameter | Type | Default | Description |
|---|---|---|---|
snapshot | integer | 0 | Controls initial orderbook snapshot delivery when subscribing to differential depth streams |
cancelOnDisconnect | boolean | false | Automatically cancel all open orders when the WebSocket session disconnects |
Snapshot Parameter
The snapshot parameter controls whether an initial orderbook snapshot is sent when subscribing to differential depth streams ({symbol}@depth, {symbol}@depth@100ms).
Connection URL example:
Code
snapshot Value | Behavior |
|---|---|
Not specified / 0 | No snapshot — only incremental updates (default) |
-1 (or any negative) | Full orderbook snapshot sent immediately on subscribe |
Positive integer (e.g., 100) | Top N levels snapshot sent on subscribe |
Use snapshot=-1 to receive a full orderbook snapshot immediately when subscribing to differential depth streams. This is useful for initializing your local orderbook state without needing a separate REST API call.
Cancel On Disconnect Parameter
The cancelOnDisconnect parameter enables automatic cancellation of all your open orders when the WebSocket session disconnects. This is a safety feature that helps prevent unwanted exposure from stale orders if your connection drops unexpectedly.
Connection URL example:
Code
cancelOnDisconnect Value | Behavior |
|---|---|
Not specified / false | Orders remain active after disconnect (default) |
true | All open orders are automatically cancelled on disconnect |
When cancelOnDisconnect=true is enabled, all open orders placed via the WebSocket session will be cancelled upon disconnection, including orders that may have been intentionally left open. Ensure your trading strategy accounts for this behavior.
Combine multiple connection parameters using &: wss://ws.gemini.com?snapshot=-1&cancelOnDisconnect=true
Authentication
Public market data streams are available without authentication. Authenticated streams (order events, trading) require either an HMAC-signed API key or an OAuth 2.0 bearer token passed on the WebSocket upgrade. See Authentication for details.