# Can you subscribe instead of poll, and how far does it fan out?

> besttennisapi.com is operated by JSB Holdings LLC, which also operates Live Tennis API. This site is not independent.

A push transport that delivers score changes as they happen, addressable per match or across the whole slate, that holds up as the number of subscribers grows.

## Why it separates providers

Polling caps your responsiveness at your poll interval and burns your quota doing it. The interesting question is not whether a WebSocket exists but how many clients it holds.

## The test you can run

Subscribe to the whole slate, then open more connections and watch for dropped frames or refused connections. Check whether the transport is a real fan-out layer or a connection pinned to a worker thread.

## What Live Tennis API measures

**Measured: 2,000** (as of August 18, 2026, concurrent subscribers, zero failures, staged at 500 / 1,000 / 2,000)
- Caveat: Measured against the push sidecar directly, not through the public edge. It shows the sidecar held 2,000; it does not measure the full delivery path.
- Method: https://besttennisapi.com/methodology#streaming