WebP: The WebPage Compression Format

Original Article ↗ Hacker News Discussion ↗

Novel use of WebP for HTML compression

  • Many readers find the “HTML inside WebP” trick clever, fun, and reminiscent of demoscene polyglots and self-extracting ZIP/PNG/HTML hacks.
  • Several see it explicitly as an experiment or art project, not something to ship on serious sites.
  • Others note similar prior experiments (e.g., polyglot HTML/ZIP/PNG, using Brotli via fonts) and appreciate the creativity.

Performance, latency, and TCP details

  • Strong pushback on the claim that a ~50 kB saving meaningfully cuts load time on typical connections.
  • Multiple comments stress that latency and TCP congestion windows dominate; for these sizes, fewer bytes often do not reduce round-trips.
  • Decompression and JS execution time, plus blocking of streaming HTML and parallel resource discovery, can offset or outweigh transfer savings.
  • Some note that savings might matter on extremely slow or high-latency links (EDGE, Mars), but not for most users.

Browser compatibility, JS/WebGL, and accessibility

  • The technique breaks on browsers or hardened configs that disable WebGL, canvas, or JS; several report the article cutting off mid-page.
  • Critics argue this violates progressive enhancement and universal accessibility expectations for the web.
  • The author apparently provides a separate no-JS version, but readers still see the main path as fragile.

Alternative compression formats (Brotli, zstd, etc.)

  • Discussion around Brotli vs gzip vs zstd:
    • Brotli offers better compression but slower encoding; good for precompressed static sites.
    • zstd is praised for tooling, portability, and maturity; some want it and Brotli widely supported in browsers.
    • There’s disappointment that Brotli isn’t exposed via browser CompressionStream for general use.

WebP as an image format

  • Some argue WebP is now widely supported across browsers and tools; others still encounter gaps (older Linux viewers, some web apps).
  • One practitioner reports large real-world size savings when switching from JPEG to WebP, with minimal complaints.
  • Others caution that very large WebP vs JPEG savings often come from quality loss, not magical compression.

Fonts, icons, and real-world bloat

  • Several point out the irony of extreme HTML micro-optimizations while shipping large webfonts and icon CSS (hundreds of kB).
  • Broader complaint: many sites waste far more bandwidth on images, fonts, and JS than they save with fine-grained text compression tricks.