Total
6.37 MB
153 requests
100% of total size
https://www.amazon.co.uk/
See the website health and performance test results for https://www.amazon.co.uk/, including status code, load speed, SSL, WHOIS, DNS, console logs, Chrome UX Report, resource sizes, and Pagespeed findings.
Tested on 1 May 2026 15:25:04.
Up
- HTTP status 200
- Response time 1.09 s
- Document load time 0 ms
- Full page load time 0 ms
- Document size 0 B
- Full page size 0 B
56/100
- Mobile score 56
- Desktop score 89
Observer's Performance Suggestions
Priority actions Observer identified from this test to improve speed, reliability, and user experience.
Slow server response (1086 ms)
Warning
Medium Server took 1.086 seconds to respond. Investigate backend latency or upstream timeouts. Read more |
No MX records configured
Warning
Medium Email cannot be delivered to this domain. Add MX records if you intend to receive mail. Read more |
Fewer than two nameservers
Warning
Medium A single nameserver is a single point of failure. Configure at least two NS records on different networks. Read more |
Desktop performance needs improvement (89/100)
Warning
Medium Score is below 90. Tackle the highest-impact audits to push into the green. Read more |
Mobile performance needs improvement (56/100)
Warning
Medium Score is below 90. Tackle the highest-impact audits to push into the green. Read more |
Fewer than 75% of users have a good Cumulative Layout Shift
Warning
Medium Only 75% of real-user samples fall in the "good" bucket for Cumulative Layout Shift. Read more |
Reduce initial server response time
Info
High Reduce time to first byte by speeding up backend processing or caching. Read more |
Reduce unused JavaScript
Info
Medium Strip JavaScript that the page does not use to reduce parse and download time. Read more |
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16 Jan 2027
241 days left
Whois
- Registrar
- Amazon.com, Inc. [Tag = AMAZON-COM]
SSL
- Issuer
- C=US,O=Amazon,CN=Amazon RSA 2048 M04
- Subject
- CN=www.amazon.co.uk
- TLS version
- TLSv1.3
- Self-signed
- No
- Valid until
- 16 Jan 2027
DNS Records
Current DNS records returned for this domain at the time of the test.
- 18.165.62.8
- 2600:9000:2467:e400:15:c9dc:596:d01
- 2600:9000:2467:e00:15:c9dc:596:d01
- 2600:9000:2467:e000:15:c9dc:596:d01
- 2600:9000:2467:6800:15:c9dc:596:d01
- 2600:9000:2467:6600:15:c9dc:596:d01
- 2600:9000:2467:c400:15:c9dc:596:d01
- 2600:9000:2467:7000:15:c9dc:596:d01
- 2600:9000:2467:8200:15:c9dc:596:d01
- tp.bfbdc3ca1-frontier.amazon.co.uk
No records returned.
No records returned.
No records returned.
Resource Summary
Transfer size share of the tested page split by resource type.
Media
3.59 MB
2 requests
56% of total size
Image
905.62 KB
69 requests
14% of total size
Font
723.6 KB
21 requests
11% of total size
Script
592.89 KB
32 requests
9.1% of total size
Document
408.52 KB
2 requests
6.3% of total size
Other
124 KB
16 requests
1.9% of total size
Stylesheet
83.26 KB
11 requests
1.3% of total size
Third-party
6.37 MB
153 requests
100% of total size
Total
5.57 MB
353 requests
100% of total size
Image
4.28 MB
289 requests
77% of total size
Font
637.09 KB
20 requests
11% of total size
Script
355.47 KB
16 requests
6.2% of total size
Document
203.6 KB
2 requests
3.6% of total size
Stylesheet
115.46 KB
9 requests
2.0% of total size
Other
14.75 KB
17 requests
0.3% of total size
Media
0 B
0 requests
0.0% of total size
Third-party
5.57 MB
353 requests
100% of total size
Core Web Vitals
Key performance signals from Lighthouse, with color-coded status for what is healthy and what still needs work.
The server starts responding quickly.
Users wait too long before any content appears.
Main visible content takes too long to appear.
Some layout movement still affects the experience.
Visual progress is slower than recommended.
Script execution still delays interactivity.
Potential input delay may still feel sluggish.
Users wait too long before the page responds.
TTFB
609 ms
FCP
4.09 s
LCP
13.61 s
TTI
14.85 s
The server starts responding quickly.
First visible content appears quickly.
Main visible content loads within the recommended range.
The layout stays visually stable while loading.
Visible content fills the page quickly.
Main thread blocking stays in a healthy range.
Potential input delay stays low.
The page becomes interactive quickly.
TTFB
164 ms
FCP
730 ms
LCP
1.59 s
TTI
2.37 s
Loading Filmstrip
Visual loading progress from the Lighthouse run, shown in time order.
Google Pagespeed Insights
Switch between desktop and mobile Lighthouse results to review the latest performance findings for this page.
Mobile
56
Desktop
89
Audit Details
| Audit | Insight | Impact |
|---|---|---|
| Layout shift culprits | Layout shifts occur when elements move absent any user interaction. Investigate the causes of layout shifts, such as elements being added, removed, or their fonts changing as the page loads. | Open |
| Minimize main-thread work | Consider reducing the time spent parsing, compiling and executing JS. You may find delivering smaller JS payloads helps with this. Learn how to minimize main-thread work | 5.1 s |
| Reduce unused JavaScript | Reduce unused JavaScript and defer loading scripts until they are required to decrease bytes consumed by network activity. Learn how to reduce unused JavaScript.
| Est savings of 271 KiB |
| Forced reflow | A forced reflow occurs when JavaScript queries geometric properties (such as offsetWidth) after styles have been invalidated by a change to the DOM state. This can result in poor performance. Learn more about forced reflows and possible mitigations.
| Open |
| LCP breakdown | Each subpart has specific improvement strategies. Ideally, most of the LCP time should be spent on loading the resources, not within delays. | Open |
| LCP request discovery | Optimize LCP by making the LCP image discoverable from the HTML immediately, and avoiding lazy-loading | Open |
| Render blocking requests | Requests are blocking the page's initial render, which may delay LCP. Deferring or inlining can move these network requests out of the critical path.
| Est savings of 1,450 ms |
| Font display | Consider setting font-display to swap or optional to ensure text is consistently visible. swap can be further optimized to mitigate layout shifts with font metric overrides.
| Est savings of 30 ms |
| Network dependency tree | Avoid chaining critical requests by reducing the length of chains, reducing the download size of resources, or deferring the download of unnecessary resources to improve page load. | Open |
| Largest Contentful Paint | Largest Contentful Paint marks the time at which the largest text or image is painted. Learn more about the Largest Contentful Paint metric | 13.6 s |
| Reduce JavaScript execution time | Consider reducing the time spent parsing, compiling, and executing JS. You may find delivering smaller JS payloads helps with this. Learn how to reduce Javascript execution time.
| 2.2 s |
| Avoid large layout shifts | These are the largest layout shifts observed on the page. Each table item represents a single layout shift, and shows the element that shifted the most. Below each item are possible root causes that led to the layout shift. Some of these layout shifts may not be included in the CLS metric value due to windowing. Learn how to improve CLS
| 8 layout shifts found |
| Time to Interactive | Time to Interactive is the amount of time it takes for the page to become fully interactive. Learn more about the Time to Interactive metric. | 14.8 s |
| First Contentful Paint | First Contentful Paint marks the time at which the first text or image is painted. Learn more about the First Contentful Paint metric. | 4.1 s |
| Image elements do not have explicit `width` and `height` | Set an explicit width and height on image elements to reduce layout shifts and improve CLS. Learn how to set image dimensions
| Open |
| Avoid enormous network payloads | Large network payloads cost users real money and are highly correlated with long load times. Learn how to reduce payload sizes.
| Total size was 6,519 KiB |
| Use efficient cache lifetimes | A long cache lifetime can speed up repeat visits to your page. Learn more about caching.
| Est savings of 5 KiB |
| Improve image delivery | Reducing the download time of images can improve the perceived load time of the page and LCP. Learn more about optimizing image size
| Est savings of 283 KiB |
| Reduce unused CSS | Reduce unused rules from stylesheets and defer CSS not used for above-the-fold content to decrease bytes consumed by network activity. Learn how to reduce unused CSS.
| Est savings of 172 KiB |
| Legacy JavaScript | Polyfills and transforms enable older browsers to use new JavaScript features. However, many aren't necessary for modern browsers. Consider modifying your JavaScript build process to not transpile Baseline features, unless you know you must support older browsers. Learn why most sites can deploy ES6+ code without transpiling
| Est savings of 6 KiB |
| Speed Index | Speed Index shows how quickly the contents of a page are visibly populated. Learn more about the Speed Index metric. | 4.9 s |
| Max Potential First Input Delay | The maximum potential First Input Delay that your users could experience is the duration of the longest task. Learn more about the Maximum Potential First Input Delay metric. | 180 ms |
| Total Blocking Time | Sum of all time periods between FCP and Time to Interactive, when task length exceeded 50ms, expressed in milliseconds. Learn more about the Total Blocking Time metric. | 240 ms |
| Cumulative Layout Shift | Cumulative Layout Shift measures the movement of visible elements within the viewport. Learn more about the Cumulative Layout Shift metric. | 0.103 |
Audit Details
| Audit | Insight | Impact |
|---|---|---|
| Forced reflow | A forced reflow occurs when JavaScript queries geometric properties (such as offsetWidth) after styles have been invalidated by a change to the DOM state. This can result in poor performance. Learn more about forced reflows and possible mitigations.
| Open |
| Render blocking requests | Requests are blocking the page's initial render, which may delay LCP. Deferring or inlining can move these network requests out of the critical path.
| Est savings of 230 ms |
| Improve image delivery | Reducing the download time of images can improve the perceived load time of the page and LCP. Learn more about optimizing image size
| Est savings of 1,282 KiB |
| Minimize main-thread work | Consider reducing the time spent parsing, compiling and executing JS. You may find delivering smaller JS payloads helps with this. Learn how to minimize main-thread work | 3.9 s |
| Network dependency tree | Avoid chaining critical requests by reducing the length of chains, reducing the download size of resources, or deferring the download of unnecessary resources to improve page load. | Open |
| Reduce initial server response time | Keep the server response time for the main document short because all other requests depend on it. Learn more about the Time to First Byte metric.
| Root document took 610 ms |
| Reduce JavaScript execution time | Consider reducing the time spent parsing, compiling, and executing JS. You may find delivering smaller JS payloads helps with this. Learn how to reduce Javascript execution time.
| 1.4 s |
| LCP request discovery | Optimize LCP by making the LCP image discoverable from the HTML immediately, and avoiding lazy-loading | Open |
| Document request latency | Your first network request is the most important. Reduce its latency by avoiding redirects, ensuring a fast server response, and enabling text compression. | Est savings of 510 ms |
| Font display | Consider setting font-display to swap or optional to ensure text is consistently visible. swap can be further optimized to mitigate layout shifts with font metric overrides.
| Est savings of 30 ms |
| Reduce unused JavaScript | Reduce unused JavaScript and defer loading scripts until they are required to decrease bytes consumed by network activity. Learn how to reduce unused JavaScript.
| Est savings of 146 KiB |
| Minify JavaScript | Minifying JavaScript files can reduce payload sizes and script parse time. Learn how to minify JavaScript.
| Est savings of 11 KiB |
| Reduce unused CSS | Reduce unused rules from stylesheets and defer CSS not used for above-the-fold content to decrease bytes consumed by network activity. Learn how to reduce unused CSS.
| Est savings of 143 KiB |
| Legacy JavaScript | Polyfills and transforms enable older browsers to use new JavaScript features. However, many aren't necessary for modern browsers. Consider modifying your JavaScript build process to not transpile Baseline features, unless you know you must support older browsers. Learn why most sites can deploy ES6+ code without transpiling
| Est savings of 12 KiB |
| Use efficient cache lifetimes | A long cache lifetime can speed up repeat visits to your page. Learn more about caching.
| Est savings of 4 KiB |
| Avoid enormous network payloads | Large network payloads cost users real money and are highly correlated with long load times. Learn how to reduce payload sizes.
| Total size was 5,705 KiB |
| Speed Index | Speed Index shows how quickly the contents of a page are visibly populated. Learn more about the Speed Index metric. | 2.3 s |
| Largest Contentful Paint | Largest Contentful Paint marks the time at which the largest text or image is painted. Learn more about the Largest Contentful Paint metric | 1.6 s |
Chrome UX Report
Real-user experience shares from recent Chrome visits to this website.
Origin: https://www.amazon.co.uk
Mobile 55.6%
Desktop 39.3%
Tablet 5.1%
| Metric | User experience share | 75th percentile |
|---|---|---|
| LCP |
Good 88.2%
Needs improvement 7.9%
Poor 3.9% | 1.68 s |
| INP |
Good 79.8%
Needs improvement 13.4%
Poor 6.9% | 161 ms |
| CLS |
Good 74.7%
Needs improvement 13.2%
Poor 12.1% | 0.10 |
| FCP |
Good 90.3%
Needs improvement 6.1%
Poor 3.6% | 1.01 s |
| TTFB |
Good 80.9%
Needs improvement 13.6%
Poor 5.4% | 618 ms |
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