Page weight analyzer. Bytes by type.
Enter a URL. We pull PSI's resource-summary audit and show total page weight broken down by type (HTML, CSS, JS, image, font, third-party) plus a per-type verdict and fix recommendation.
Enter a URL. We pull Google PSI's resource-summary audit and show total page weight broken down by type (HTML, CSS, JS, image, font, media, third-party) with per-type budget verdicts and fix recommendations.
Sources used
- Google PSI v5 API — resource-summary audit source
- HTTP Archive page weight reports — median + percentile benchmarks
- web.dev performance budgets
URL is sent only to Google PSI. Digital Heroes does not log queries.
Privacy: URL is sent only to Google PSI.
Bytes are a budget.
Median page weight on the public web has grown to roughly 2.5MB on mobile per HTTP Archive's annual crawl. But median is not target — the 1.5MB threshold separates fast-feeling from slow-feeling sites on 4G. Per-type budgets that work for most sites: HTML under 100KB, CSS under 150KB, JS under 350KB, images under 800KB, fonts under 200KB. The analyzer above shows the breakdown plus per-type budget gap so you know where bytes are leaking.
Three rules for byte budgets. JavaScript is the most expensive byte (parse + execute cost on top of transfer); the JS budget is therefore the tightest. Images compress well to AVIF / WebP — the image-byte budget is generous because of this. Third-party scripts are usually the easiest cleanup target — most sites have 30%+ dormant tag-manager tags that ship to every visitor for zero benefit. The web.dev performance budgets guide is the canonical reference.
Tools in the same cluster: JavaScript Size Checker for the JS-only deep dive. Render Blocking Checker for the critical-path resource view. Lighthouse Score Checker for the broader performance grade.
Five answers.
What's a healthy page weight in 2026?
Median page weight per HTTP Archive's 2024-2025 mobile crawl is roughly 2.5MB — but median is not target. The ~1.5MB threshold separates fast-feeling from slow-feeling sites on 4G. Per-type budgets that work for most sites: HTML under 100KB, CSS under 150KB, JS under 350KB, images under 800KB total (with lazy-loading below the fold), fonts under 200KB. Going significantly above any one budget without a deliberate trade-off (e.g., font-heavy editorial sites) usually means there is unminified or unused code shipping.
Why does JavaScript weight hurt the most?
JavaScript blocks rendering during parse + execute, not just transfer. 350KB of JS takes 1.5-3 seconds to parse + execute on a mid-tier mobile (the device profile PSI throttles to). The same 350KB as images causes maybe 200ms perceived delay (lazy-loading helps further). The byte budget for JS is therefore much tighter than other resource types. The analyzer above flags JS over 500KB as a red-zone signal.
Third-party weight — what's it doing on my site?
Third-party scripts (analytics, ads, chat widgets, A/B testing, tag managers) commonly add 200KB-1MB of un-budgeted weight. Each tag is typically 30-150KB plus the entities they pull in. Audit third-party weight quarterly: load time impact, value delivered, replacement options. Tag-management tools often cleanup-target 30% of dormant third-party tags. Prioritize ones that load synchronously over async ones — synchronous tags block rendering far worse than async equivalents.
How does this differ from Lighthouse?
The Lighthouse Score Checker shows the broader Performance grade across 30+ audits. Page Weight Analyzer focuses specifically on the resource-summary audit — the answer to 'where are my bytes going?'. Use Lighthouse for the comprehensive performance grade; use Page Weight Analyzer when you specifically need the per-type byte breakdown to plan a weight-reduction sprint.
Does this tool save my data?
The URL is sent only to Google's public PageSpeed Insights API. Nothing is logged on Digital Heroes servers.
Page over 2.5MB?
Our web development engagements run a per-type byte audit, identify the top 3 weight offenders, and ship a 4-week reduction sprint targeting LCP + INP improvement.
Published · Last updated .