3.6 sec in total
293 ms
2.5 sec
825 ms
Welcome to costco.co.uk homepage info - get ready to check Costco best content for United Kingdom right away, or after learning these important things about costco.co.uk
Shop at Costco.co.uk for best deals on all products and enjoy low warehouse prices on name-brand products online and instore. Delivery included.
Visit costco.co.ukWe analyzed Costco.co.uk page load time and found that the first response time was 293 ms and then it took 3.4 sec to load all DOM resources and completely render a web page. This is a poor result, as 55% of websites can load faster.
costco.co.uk performance score
name
value
score
weighting
Value3.4 s
38/100
10%
Value9.3 s
1/100
25%
Value4.6 s
70/100
10%
Value590 ms
50/100
30%
Value0.546
13/100
15%
Value7.3 s
49/100
10%
293 ms
393 ms
174 ms
175 ms
188 ms
Our browser made a total of 90 requests to load all elements on the main page. We found that 60% of them (54 requests) were addressed to the original Costco.co.uk, 33% (30 requests) were made to Media.costco.co.uk and 3% (3 requests) were made to Warehouses.costco.co.uk. The less responsive or slowest element that took the longest time to load (847 ms) belongs to the original domain Costco.co.uk.
Page size can be reduced by 747.1 kB (40%)
1.9 MB
1.1 MB
In fact, the total size of Costco.co.uk main page is 1.9 MB. This result falls beyond the top 1M of websites and identifies a large and not optimized web page that may take ages to load. 65% of websites need less resources to load. Images take 909.4 kB which makes up the majority of the site volume.
Potential reduce by 165.2 kB
HTML content can be minified and compressed by a website’s server. The most efficient way is to compress content using GZIP which reduces data amount travelling through the network between server and browser. This page needs HTML code to be minified as it can gain 50.9 kB, which is 27% of the original size. It is highly recommended that content of this web page should be compressed using GZIP, as it can save up to 165.2 kB or 88% of the original size.
Potential reduce by 28.8 kB
Image size optimization can help to speed up a website loading time. The chart above shows the difference between the size before and after optimization. Costco images are well optimized though.
Potential reduce by 405.5 kB
It’s better to minify JavaScript in order to improve website performance. The diagram shows the current total size of all JavaScript files against the prospective JavaScript size after its minification and compression. It is highly recommended that all JavaScript files should be compressed and minified as it can save up to 405.5 kB or 70% of the original size.
Potential reduce by 147.5 kB
CSS files minification is very important to reduce a web page rendering time. The faster CSS files can load, the earlier a page can be rendered. Costco.co.uk needs all CSS files to be minified and compressed as it can save up to 147.5 kB or 81% of the original size.
Number of requests can be reduced by 43 (49%)
87
44
The browser has sent 87 CSS, Javascripts, AJAX and image requests in order to completely render the main page of Costco. We recommend that multiple CSS and JavaScript files should be merged into one by each type, as it can help reduce assets requests from 30 to 1 for JavaScripts and from 15 to 1 for CSS and as a result speed up the page load time.
costco.co.uk
293 ms
www.costco.co.uk
393 ms
cookies
174 ms
reset.css
175 ms
magiczoom.css
188 ms
facebox.css
189 ms
styles-min.css
280 ms
jquery-ui.css
192 ms
cookiecuttr.css
256 ms
megafish.css
256 ms
client.css
278 ms
modernizr-2.5.3.js
303 ms
jquery-1.7.1.min.js
357 ms
jquery-ui.min.js
503 ms
jquery.form.pack.js
345 ms
magiczoom.js
374 ms
jcarousellite-1.0.1.min.js
374 ms
jquery.center.js
372 ms
facebox.js
420 ms
json2.pack.js
437 ms
quicklive-JS-resources-min.js
454 ms
tracking-resources.js
456 ms
jquery.hoverIntent.minified.js
448 ms
jquery.equalheights.js
533 ms
jquery.lazyload.js
534 ms
jquery.scrollTo-1.4.1-min.js
539 ms
jquery.ui.widget.js
539 ms
jquery.ui.datepicker.min.js
540 ms
jquery.ui.selectmenu.js
573 ms
jquery.usermode.js
579 ms
jquery.cookie.js
596 ms
jquery.cookiecuttr.js
628 ms
jquery.cookie.js
629 ms
jquery.persist.js
626 ms
quicklive-addressComponent-resources.js
651 ms
hoverIntent.js
658 ms
superfish.js
674 ms
bootstrap.min.js
6 ms
prodoverride.css
318 ms
HPstyle.css
256 ms
HPsliderstyle.css
255 ms
jquery.coda-slider-3.0.js
256 ms
tyrestyle.css
524 ms
cc_footer.css
245 ms
google-siteCatalyst-resources.js
668 ms
home_services.jpg
53 ms
home_topspot1v2.jpg
53 ms
home_topspot2v2.jpg
69 ms
home_topspot3V2.jpg
53 ms
home_topspot4.jpg
51 ms
home_topspot5.jpg
52 ms
home_bigbox1.jpg
69 ms
home_bigbox2.jpg
52 ms
home_whatsnew.jpg
52 ms
home_hotbuy.jpg
61 ms
home_register.jpg
67 ms
home_feat1.jpg
70 ms
home_feat10.jpg
54 ms
home_feat3v3.jpg
53 ms
home_feat4.jpg
60 ms
home_feat5.jpg
54 ms
home_feat6.jpg
54 ms
home_feat7.jpg
55 ms
home_feat8.jpg
57 ms
home_feat9.jpg
57 ms
home_feat2.jpg
59 ms
home_feat11.jpg
59 ms
home_feat12.jpg
58 ms
headerLinearBg.png
103 ms
costco-logo.png
104 ms
costco-wholesale-topnav.jpg
103 ms
michelin_logo.jpg
102 ms
searchIcon.png
102 ms
amexlearnbtn.jpg
100 ms
8802980823070.jpg
164 ms
basketIcon.png
150 ms
dc.js
30 ms
print.css
847 ms
slide.png
169 ms
__utm.gif
98 ms
prevarrowlft.png
90 ms
nextarrowrgt.png
89 ms
currentslide.png
91 ms
ui-icons_ffffff_256x240.png
100 ms
UK-flag.gif
101 ms
US-flag.gif
101 ms
CN-flag.gif
117 ms
MX-flag.gif
116 ms
KR-flag.gif
91 ms
ajax-loader.gif
241 ms
costco.co.uk accessibility score
Names and labels
These are opportunities to improve the semantics of the controls in your application. This may enhance the experience for users of assistive technology, like a screen reader.
Impact
Issue
Buttons do not have an accessible name
Links do not have a discernible name
Contrast
These are opportunities to improve the legibility of your content.
Impact
Issue
Background and foreground colors do not have a sufficient contrast ratio.
Navigation
These are opportunities to improve keyboard navigation in your application.
Impact
Issue
[id] attributes on active, focusable elements are not unique
ARIA
These are opportunities to improve the usage of ARIA in your application which may enhance the experience for users of assistive technology, like a screen reader.
Impact
Issue
ARIA IDs are not unique
Tables and lists
These are opportunities to improve the experience of reading tabular or list data using assistive technology, like a screen reader.
Impact
Issue
Lists do not contain only <li> elements and script supporting elements (<script> and <template>).
costco.co.uk best practices score
Trust and Safety
Impact
Issue
Does not use HTTPS
Includes front-end JavaScript libraries with known security vulnerabilities
Ensure CSP is effective against XSS attacks
User Experience
Impact
Issue
Serves images with low resolution
General
Impact
Issue
Detected JavaScript libraries
Missing source maps for large first-party JavaScript
costco.co.uk SEO score
Crawling and Indexing
To appear in search results, crawlers need access to your app.
Impact
Issue
Links are not crawlable
Content Best Practices
Format your HTML in a way that enables crawlers to better understand your app’s content.
Impact
Issue
Document doesn't have a valid hreflang
Mobile Friendly
Make sure your pages are mobile friendly so users don’t have to pinch or zoom in order to read the content pages. [Learn more](https://developers.google.com/search/mobile-sites/).
Impact
Issue
Document uses legible font sizes
Tap targets are not sized appropriately
EN
N/A
UTF-8
Language claimed in HTML meta tag should match the language actually used on the web page. Otherwise Costco.co.uk can be misinterpreted by Google and other search engines. Our service has detected that English is used on the page, and neither this language nor any other was claimed in <html> or <meta> tags. Our system also found out that Costco.co.uk main page’s claimed encoding is utf-8. Use of this encoding format is the best practice as the main page visitors from all over the world won’t have any issues with symbol transcription.
costco.co.uk
Open Graph data is detected on the main page of Costco. This is the best way to make the web page social media friendly. Here is how it looks like on Facebook: