Page Size Checker

Page size is one of the most direct determinants of how fast a page loads — and load speed affects everything from user experience to search rankings to conversion rates. Page Size Checker measures the total transfer size of any URL, giving you a concrete number to work with when evaluating or optimizing a page's performance.

The number returned represents the total weight of the page's HTML, including any resources loaded inline. Large pages — anything above a few hundred kilobytes for the base HTML, or several megabytes for the full page with all assets — are worth investigating. The bloat usually comes from a few common sources: unoptimized images, render-blocking JavaScript, unused CSS loaded from plugins or frameworks, or third-party scripts added for analytics, chat widgets, and advertising.

For anyone working on Core Web Vitals improvements, page size is a starting point. It doesn't tell you everything, but a page that's inexplicably large almost always has an underlying issue that explains the performance problem. Knowing the number gives you a baseline to measure against after you've made optimizations.

E-commerce sites and landing pages are where this matters most commercially. Research consistently shows that load time has a direct relationship with bounce rate — pages that take too long to load see significantly higher abandonment. Running a page size check as part of a pre-launch review, alongside speed tests and GZIP compression verification, is a lightweight way to catch obvious performance issues before they start costing you traffic and conversions.