Enable HTTP/2 or HTTP/3

Modern HTTP protocols significantly reduce the impact of latency and allow multiple resources to be downloaded simultaneously over a single connection, leading to much faster page loads.

Quick Reference

• Enable HTTP/2 or HTTP/3 for request multiplexing
• Eliminate the need for resource concatenation
• Reduce overhead with header compression

Check

Verify that the server is serving resources over HTTP/2 or HTTP/3 using browser DevTools or online checkers.

Fix

Enable HTTP/2 or HTTP/3 in your web server (Nginx, Apache) or via a CDN/load balancer.

Explain

Explain the advantages of HTTP/2 and HTTP/3 over HTTP/1.1, such as multiplexing and header compression.

Code Review

Review the routes, assets, and loading behavior that affect Enable HTTP/2 or HTTP/3. Flag exact files, requests, or rendering steps that add unnecessary network, CPU, or layout cost, and describe the measurement method used to confirm the issue.

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For full implementation details, code examples, and framework-specific guidance, see references/rule.md.

Rule page: https://frontendchecklist.io/en/rules/performance/http2