How many tickers can you subscribe to on a single Polygon WebSocket connection?

There is no limitation on our side to the number of tickers you can subscribe to at once as long as you can consume the data fast enough. You can subscribe to all tickers and all events simultaneously in one WebSocket feed.

You can subscribe to all tickers using the "*" character. For example, to subscribe to trades for the entire US equities universe, you can use {"action":"subscribe", "params":"T.*"}

You can also use a comma separated list of events + tickers to subscribe to a custom list of tickers/events, such as {"action":"subscribe", "params":"T.AAPL, Q.MSFT, AM.F, A.SPY"}

The maximum character limit you can insert in the subscribe message is 1MB worth of characters.