Crawl Field Notes

Response compression

Compression reduces transferred bytes when the client advertises a supported content encoding.

Atlas version atlas-2026-07-28-v1 · Section: HTTP behavior and efficiency

How it works

The server selects gzip, Brotli, or identity based on Accept-Encoding and should vary caches on that decision.

How to validate it

Measure compressed and uncompressed sizes, Content-Encoding, Vary, and total latency for representative HTML, JSON, CSS, and script bodies.

Common failure

Precompressed content with an incorrect Content-Length or missing Vary header can produce corrupted responses or cache confusion.

Machine-readable editions

The same article is available as Markdown and JSON. These alternates are linked here but are not submitted through the sitemap or IndexNow.

Related topics