HTTP/2 Push Tester

Heads up: Server Push was deprecated in Chrome 106 (Sep 2022) and removed by other major browsers. This page documents the feature and provides a checker for legacy environments.

Browser support

BrowserServer PushStatus
Chrome / Edge✗ RemovedChrome 106+ ignores PUSH_PROMISE frames
Firefox✗ RemovedDisabled by default in 81+; behind flag
Safari✗ Never shipped reliably
Node.js (http2)✓ SupportedFor server-to-server or testing only
curl✓ With --http2Use for testing the wire protocol

Use early hints (103) instead

If you want to give the browser an early signal to fetch resources, use 103 Early Hints with Link: <url>; rel=preload. Supported in Chrome 103+, Edge 103+, and works through CDNs (Cloudflare, Fastly, Akamai).

Test if a server still pushes (curl)

curl -v --http2 -o /dev/null \
  -H "Cache-Control: no-cache" \
  https://your-site.example/index.html 2>&1 | grep -i "PUSH_PROMISE"

If the output contains PUSH_PROMISE, the server is still pushing. In modern browsers this is ignored.

About this tool

HTTP/2 Push Tester is a single-purpose utility on instant.tw, a free toolbox of calculators, converters, generators, and quick lookups. Everything works in your browser — nothing is uploaded, nothing is stored on a server unless explicitly noted.

Category: Developer Tools — Advanced. Browse more Developer Tools — Advanced tools.