About this tool
Audit image preload exports before launch so true LCP candidates get early discovery while non-critical assets do not consume bandwidth and parser priority.
The Critical Image Preload Checker analyzes your page's resource hints to determine whether LCP-candidate and hero images have proper preload coverage. It detects missing preload links for above-fold images, flags over-preloading of non-critical assets that wastes bandwidth priority, and reports byte-budget violations when too many images compete for early network slots. The result is a clear action list ranked by LCP impact.
- Parses rows in URL|image|preload|fetchpriority|context|size|media format and normalizes URLs with an optional base URL.
- Flags critical images missing preload hints, missing fetchpriority=high, and conflicting directives such as preload plus low priority.
- Detects duplicate per-page preloads plus count and byte-budget overflow to prevent over-preloading regressions.
How to use Image Preload Checker
Enter a URL and the tool identifies which images are likely LCP candidates based on viewport position and rendered size, then checks the document head for corresponding preload link elements. It reports gaps where critical images lack preload hints and excess entries where below-fold images consume early priority. Apply the recommended changes, then re-run the audit to confirm your preload budget is focused on the assets that matter most.
When this tool is useful
- Audit image preload hints before launching template updates that touch LCP and hero-image rendering.
- Catch missing preload coverage for critical images and over-preloading of non-critical assets in one pass.
- Prioritize pages where preload count or byte budgets are exceeded and likely competing with essential resources.
Practical tips
- Use preload on truly critical LCP candidates only, then pair those rows with fetchpriority=high for clearer browser prioritization.
- Set per-page preload count and byte budgets to prevent template regressions that silently overuse preload hints.
- Avoid duplicate preloads for the same asset and remove below-fold image preloads unless you have measured evidence they are needed.
Why people use this tool
Without a preload hint, the browser cannot begin fetching an LCP image until it has parsed the HTML, built the render tree, and discovered the resource in markup or CSS. That discovery delay directly inflates Largest Contentful Paint times, especially on slower connections. Conversely, over-preloading non-critical images can saturate early bandwidth and push truly important resources later in the queue, making disciplined preload management essential for fast page loads.
Related search intents
critical image preload checker, preload image seo checker, rel preload image audit, lcp preload validator.