Page Size Checker

Why page size matters

Every kilobyte on a page has to be downloaded before the visitor sees it. Heavy pages load slowly, especially on mobile data, and slow pages lose visitors. Page weight also affects Core Web Vitals such as Largest Contentful Paint, which Google uses as part of its page experience signals. You can read more about these metrics on web.dev.

This page size checker downloads the HTML of a page and every file it links to directly:

• Images (<img> tags)
• JavaScript files
• CSS stylesheets
• the favicon and other linked files

It adds up the total, shows a breakdown by type with a colored bar and lists the largest files first, so you know exactly where to start.

How to check page size

1. Enter the URL of the page and click Check page size.
2. Wait a few seconds while up to 80 files are measured.
3. Look at the total and the verdict: under about 1.5 MB is light, 1.5-3 MB is average, above 3 MB is heavy.
4. Scroll to Largest files and work through the list from the top.

How to make your pages lighter

• Compress and resize images. This is usually the biggest win. A photo straight from a phone can be 4 MB, while a web-ready version is often under 200 KB. Use our free Image Compressor and Image Resizer.
• Use modern formats like WebP. Convert files with the Image Converter.
• Remove unused plugins and scripts. Every slider, chat widget and tracking tag adds weight.
• Turn on compression (gzip or Brotli) on your server. Check it with the HTTP Header Checker.
• Lazy-load images below the fold with loading="lazy".
• Use caching so returning visitors do not download everything again.

What this tool does not measure

Files loaded later by JavaScript or CSS, such as web fonts, background images, videos and ads, are not counted, because they are not linked in the HTML. Sizes are what our server downloaded, which is the compressed size when your server uses gzip or Brotli. For a full lab test, use Google's PageSpeed Insights alongside this tool.

For a broader health check, run our Website SEO Audit, which also looks at response time and compression.

What makes a page heavy

The total size of a page is the sum of everything the browser downloads: the HTML, CSS, JavaScript, images, fonts and any third-party files. On most websites, images and JavaScript are the biggest parts. A single uncompressed photo straight from a phone can be 3-5 MB, more than an entire well-built page should weigh.

According to the HTTP Archive Web Almanac, the typical mobile page has grown to around 2 MB over the past decade, so a lighter page gives you a real advantage, especially for visitors on slow or expensive mobile data.

Page size and Core Web Vitals

Google measures real-world experience with Core Web Vitals:

• Largest Contentful Paint (LCP): how quickly the main content appears. Big hero images and slow servers hurt it.
• Interaction to Next Paint (INP): how quickly the page responds to taps and clicks. Heavy JavaScript hurts it.
• Cumulative Layout Shift (CLS): how much the layout jumps while loading. Images without dimensions and late ads hurt it.

A smaller page does not guarantee good scores, but it makes them much easier to reach.

A practical page weight budget

These are guidelines, not hard limits. A photography portfolio will be heavier than a contact page. The point is to set a budget and notice when a change breaks it.

Quick wins to reduce page size

1. Compress and resize images with the Image Compressor and Image Resizer.
2. Serve WebP instead of PNG or large JPG files using the Image Converter.
3. Turn on gzip or Brotli compression on the server. Check the result with the HTTP Header Checker.
4. Remove unused plugins and scripts, such as old sliders, chat widgets you do not use or several analytics tools doing the same job.
5. Lazy-load images below the fold with loading="lazy".
6. Limit web fonts to the weights you actually use.

Measure, change, measure again

Check the page here, make one change, and check again. For a complete performance report including Core Web Vitals from real Chrome users, run PageSpeed Insights as well. Then use the Website SEO Audit to make sure the speed work did not break titles, headings or other SEO basics.

Example: finding what slows down a homepage

A business homepage measures 6.8 MB. The breakdown shows images make up 5.9 MB, mainly three slider photos uploaded straight from a camera at over 1.5 MB each. Resizing them to 1920 px wide and saving as WebP at quality 75 brings each to a fraction of that size, and removing an unused video background script saves more. Checking again, the page is under 1.5 MB and loads noticeably faster on mobile data.

Last updated: October 25, 2026