Support 103 Early Hints informational responses for navigation. When a 103 response includes <link rel=preload> or other link headers Chromium tries to preload (and/or preconnect, prefetch) specified resources even before the final response is received. This gives Web developers a way to optimize Core Web Vitals such as Largest Contentful Paint (LCP).

Motivation

A few months ago, we announced a collaborative experiment [1] to measure the potential impact of 103 early hints. The results indicate that Early Hints could result in speed improvements on the order of a few hundred milliseconds (the sample size is a bit small though). Given these encouraging results, we are now moving forward with the next steps, starting with this intent to prototype. [1] https://chromium.googlesource.com/chromium/src/+/master/docs/early-hints.md

Documentation

Specification

Editor's draft

Status in Chromium

Internals>Preload


In development (tracking bug)

Consensus & Standardization

After a feature ships in Chrome, the values listed here are not guaranteed to be up to date.

  • No signal
  • No signal
  • No signal
  • Positive

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Comments

Last updated on 2021-02-18