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HTTP 103 Early Hints — What It Means & How to Fix It

Informational1xx informational

Overview

The HTTP 103 Early Hints status code allows the server to send preliminary response headers before the final response, enabling the browser to start preloading resources.

Key Details

  • This status code lets the server hint at resources the browser should preload while the final response is being prepared.
  • It improves page load performance by allowing early resource fetching.
  • Commonly used with Link headers to specify resources like stylesheets or scripts.
  • Supported by modern browsers like Chrome and Firefox.
  • The final response follows with the actual status code and body.

Common Causes

  • Server wants to speed up page loads by hinting at critical resources early.
  • CDN or reverse proxy sends early hints while the origin server prepares the response.
  • Performance optimization for pages with known critical resources.

Steps

  1. 1Configure your server or CDN to send 103 Early Hints with Link headers for critical resources.
  2. 2Identify key resources like CSS, fonts, and JavaScript that benefit from preloading.
  3. 3Test browser support and verify resources are being preloaded correctly.
  4. 4Monitor performance improvements using browser developer tools.

Tags

httpinformationalperformancepreloadearly-hints

Related Items

http-100-continuehttp-101-switching-protocolshttp-102-processing

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http-102-processingHTTP 102 Processing — What It Means & How to Fix It
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http-100HTTP 100 Continue — What It Means
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http-101HTTP 101 Switching Protocols Explained
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http-102HTTP 102 Processing — WebDAV Status
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Frequently Asked Questions

It allows the server to send Link headers before the final response, enabling the browser to start preloading critical resources like CSS and fonts earlier.