HTML document size
The size of the returned HTML in KB (and bytes), the payload the browser has to download first.
Free Website Page Size Checker
Enter a URL to measure the HTML document size, see whether the response is compressed, and count the script, stylesheet, and image requests referenced in the markup.
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Check page size
Enter a URL (or domain). NorthDuty requests it and reports the HTML size, compression, and an estimate of the requests the page makes.
Free check. No signup. Results are not published or indexed.
How NorthDuty website monitoring works
Enter a URL (or domain). NorthDuty requests it and reports the HTML size, compression, and an estimate of the requests the page makes. Recurring checks are configured inside the NorthDuty app.
What this page size checker reports
A single request shows how heavy the HTML is and how many sub-resources it pulls in.
Compression
Whether the response was served with gzip or brotli compression, and which encoding was used.
Request estimate
A count of the script, stylesheet, and image references in the HTML, plus a light / moderate / heavy rating.
Resource breakdown
Separate counts of scripts, stylesheets, and images so you can see where the weight comes from.
Why check page size
Heavy pages and long request chains slow down load times and hurt Core Web Vitals — especially on mobile connections.
- See if compression is actually enabled
- Spot an oversized HTML document
- Count how many requests the page makes
- Find script and image bloat to trim
- Get a baseline before a performance pass
How the page size checker works
No signup — enter a URL and get the size and request estimate back.
1
Enter a URL
Provide a full URL or just a domain; NorthDuty defaults to HTTPS.
2
We request the page
NorthDuty fetches the HTML, following redirects safely, and reads its size and headers.
3
We analyze the markup
The HTML is scanned for script, stylesheet, and image references to estimate the request count.
4
You get a weight report
See the HTML size, compression, and request estimate with a rating — nothing is stored.
HTML size and total page weight are not the same number
This tool measures the HTML document exactly — the first thing a browser downloads, before it knows about a single image or script — and then counts the scripts, stylesheets and images referenced in that markup to estimate how many more requests follow.
Total page weight, the number you get from a full waterfall in DevTools, includes every one of those files fully downloaded. The HTML figure still matters on its own: it arrives first, it blocks nothing else from starting, and a page whose HTML alone is 400 KB is slow before any image has loaded.
Rules of thumb for page weight
There is no official limit, and a photography portfolio will always outweigh a text page. These are the thresholds worth reacting to.
| What | Comfortable | Worth investigating | Why |
|---|---|---|---|
| HTML document | Under 100 KB | Over 200 KB | Usually a page builder inlining CSS, or a huge product grid rendered server-side |
| Compression | Gzip or Brotli on | Off | Text compresses 60–80%; serving HTML uncompressed is free performance thrown away |
| Scripts referenced | Under 15 | Over 30 | Each one is a request, and third-party ones are outside your control |
| Images on the page | Under 20 | Over 40 | Often a slider or a gallery loading everything instead of lazy-loading |
| Stylesheets | 1–3 | Over 6 | A sign of plugins each shipping their own CSS |
What usually makes a page heavy
In order of how often it turns out to be the cause.
Images at the wrong size
A 3000px photo displayed at 600px wide costs the visitor the full download. Resize on upload, serve WebP, and let the browser pick a size with srcset.
Page builders and sliders
Builder themes commonly add several stylesheets and scripts per page, and sliders load every slide up front. Both show up here as request counts, not as HTML size.
Fonts
Four weights of two families is eight files before any text renders. Two weights of one family covers most designs.
Third-party tags
Chat widgets, heatmaps, consent tools and pixels each pull their own scripts, often loading more scripts in turn. They are also the ones you cannot optimise.
Compression switched off
Usually a server or CDN misconfiguration after a migration. It is the cheapest thing on this list to fix and it affects every page at once.
Plugins left active
Every WordPress plugin that enqueues assets does so on every page by default, including the ones only used on the contact form.
Why this matters beyond the number
Weight is what turns into waiting on a phone on a mobile network, and waiting is what shows up in Core Web Vitals as a poor Largest Contentful Paint. Google measures that from real visitors, not from a test, so the fix has to hold for the slowest connections your customers actually use.
The more useful habit is watching the direction rather than the absolute figure. Pages gain weight gradually — a new script here, an unoptimised hero image there — and the month where it doubles is usually a deploy nobody connected to the slowdown.
Go Beyond One-Off Checks
Use the tool preview for a quick answer, then move into recurring monitoring for your most important pages and journeys.
Feature
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Uptime Monitoring
Monitor uptime every 5 minutes by default with HTTP, SSL, DNS, blank-page detection, broken resources, JavaScript errors, and API call tracking.
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How to Monitor Core Web Vitals
Learn how to monitor Core Web Vitals alongside website health checks, JavaScript errors, API calls, and user journeys.
Read How to Monitor Core Web VitalsArticle
How Often to Monitor Your Website
How often should you check your website? Monitoring frequency by site type, what 1, 5 and 15-minute checks mean, and how to balance speed against noise.
Read How Often to Monitor Your WebsitePricing
Pricing
NorthDuty plans are sized by how many checkout, signup and login journeys you monitor: Free, $29 Starter, $79 Pro, $199 Business. 7-day trial, no card.
Compare pricing plansFrequently Asked Questions
Answers about this diagnostic preview and when to move into recurring monitoring.
What is a good page size for a website?
As a rule of thumb, keep the HTML document under 100 KB and the number of referenced scripts under 15. Total page weight varies hugely by page type — an image-heavy landing page will always be larger than a blog post — so compare a page against its own history rather than against a universal number.
Does this checker measure total page weight?
It measures the HTML document exactly and estimates the rest from the markup: scripts, stylesheets and images referenced in the HTML. It does not download every asset, so it is a fast indicator rather than a full waterfall. For a complete breakdown use your browser's network tab.
Why is my page size so large?
Most often oversized images, then page-builder and slider assets, web fonts, third-party tags, and compression being switched off at the server or CDN. Check compression first — it is one setting and it affects every page.
Does page size affect SEO?
Indirectly. Page weight drives load time, which feeds Core Web Vitals, which is a ranking signal — and a much stronger conversion signal. A heavy page rarely loses rankings on weight alone, but it loses visitors on mobile connections.
Is this page size checker free?
Yes. It's free and requires no signup. Enter a URL and you get its HTML size and request estimate immediately.
Does it measure the full page weight?
It measures the HTML document size exactly and estimates the number of requests from the markup. It does not download every image, script, and stylesheet, so it is a fast estimate rather than a full waterfall.
How is the request count estimated?
NorthDuty counts the script, stylesheet, and image references in the returned HTML, then adds the HTML document itself. Dynamically injected resources may not be included.
What makes a page 'heavy'?
The rating combines HTML size and the estimated request count. Larger documents and many requests move a page from light to moderate to heavy.
Start monitoring your website with NorthDuty today.
Page weight creeps up with every new script and image. NorthDuty monitors performance signals continuously so regressions get caught before they slow your site down.
7 days with Pro features and limits, no credit card — then keep one daily journey on the free plan.