www.costco.com speed test — 20 Oct 2026
Measured from the wfix.shop server on 20 October 2026 at 12:36 UTC. Grade A (91/100), with the screenshots, the timings and the fixes that matter.
Where the first byte went
- DNS lookup 69 ms 33%
- TCP connect 34 ms 17%
- Server wait 102 ms 50%
Measured on the connection that fetched the HTML. Every other request on the page waits for the end of this bar before it can start.
How this page compares
Every report published here is in this comparison, so it is a reference population of pages tested from one server - not a benchmark of the whole web.
What these numbers mean
- The first byte arrived in 206 ms. That is workable, and the cheapest win left is caching or a warmer connection.
- The page transfers 1.03 MB over 26 request(s). Images files are 75% of it, so resize and recompress the largest images before anything else.
- The HTML itself arrives gzip-compressed.
- It runs over HTTP/3, so the assets share a connection instead of opening one each.
- 75% of the weight comes from other hosts (analytics, fonts, embeds), which also means their slow day becomes your slow day.
- The largest element painted at 316 ms, inside the 2.5 s Google calls good.
- Layout shift is 0.185 (good is under 0.1): something without a reserved size is loading late - an image, an ad, or a font swap.
- The main thread was blocked for 1.04 s, so taps and scrolling wait while scripts run.
Fix first: Render-blocking resources - Add defer or async to scripts that do not change the first paint, inline the critical CSS, and load the rest with media="print" plus an onload swap.
Read on one shared server, not a visitor's phone: use it to compare pages against each other, not as a promise about every connection. We fix what these tests find.
Screenshot
What the page looks like
Loaded in headless Chromium on this server. Click an image to open it full size.
Browser render
The same URL loaded in a real browser, so these are the readings curl cannot produce. The grade above is still built from the server measurements.
Page weight by type
What the page is made of
Transfer size, compressed as sent. 26 request(s) in total, 1.03 MB across all of them.
Top issues
Render-blocking resources
high impact5 render-blocking resource(s) in the document head (2 script(s), 3 stylesheet(s)). The page cannot paint until each one arrives.
Fix: Add defer or async to scripts that do not change the first paint, inline the critical CSS, and load the rest with media="print" plus an onload swap.
Total page weight
medium impactThe page transfers 1.03 MB across 26 request(s), with the document itself at 266.5 KB.
Fix: Work through the heaviest assets first: images, then fonts, then third-party scripts.
Third-party weight
medium impact1 third-party host(s) serve 785.7 KB of this page. Each one is another DNS lookup, TLS handshake and point of failure you do not control.
Fix: Self-host the libraries you can, drop the tags you cannot justify, and preconnect the ones you keep.
HTML document size
medium impactThe document transfers 266.5 KB. A bloated document delays every other request, because nothing else can start until it is parsed.
Fix: Paginate long listings, move repeated markup into a template, and stop inlining large data URIs into the HTML.
Avoid extra redirects
medium impact1 redirect hop(s) before the page load started, each one a full round trip before the first byte.
Fix: Link to the canonical URL (and make sure http, the apex domain and www all point at it) so no visitor pays a redirect first.
Waterfall
Slowest requests
Each bar is one request's own response time, scaled to the slowest. Assets were fetched in parallel, so the bars overlap in real time rather than stacking. first party third party
| Request | Type | Status | Time | Size |
|---|---|---|---|---|
| https://gdx-assets.costco.com/adobe/assets/urn:aaid:aem:48f1f1b9-89ab-4280-bdbe-163ae328b952/as/d_27w460623_banner_nov_mvm.avif?width=320 3rd party | images | 200 | 1.01 s | 14.1 KB |
| https://gdx-assets.costco.com/adobe/assets/urn%3Aaaid%3Aaem%3A2bf6a432-5e6d-4d70-9433-702565ddbb36/as/26w05292_hp_icon_new_lower_prices.avif?width=320 3rd party | images | 200 | 982 ms | 20.0 KB |
| https://gdx-assets.costco.com/adobe/assets/urn%3Aaaid%3Aaem%3A4c0e7b4c-1cf8-4f38-8f92-a9a0da781b2d/as/26w05292_hp_icon_this_week.avif?width=320 3rd party | images | 200 | 978 ms | 37.6 KB |
| https://gdx-assets.costco.com/adobe/assets/urn%3Aaaid%3Aaem%3Af45b3844-c2c8-4df6-bd4c-837cdaa44cc0/as/26w05292_hp_icon_treasure_hunt.avif?width=320 3rd party | images | 200 | 962 ms | 21.7 KB |
| https://gdx-assets.costco.com/adobe/assets/urn:aaid:aem:700b4244-1830-4bb4-8c15-89ec75777531/as/Costco-logo-HEX.avif 3rd party | images | 200 | 928 ms | 37.7 KB |
| https://gdx-assets.costco.com/adobe/assets/urn:aaid:aem:192f1664-4797-4075-ada3-07e10a59c362/as/m_27w460623_banner_nov_mvm.avif 3rd party | images | 200 | 911 ms | 123.9 KB |
| https://gdx-assets.costco.com/adobe/assets/urn%3Aaaid%3Aaem%3A44822626-7e58-47df-b18c-b46f76dbc506/as/26w10169_hp_icon_services.avif?width=320 3rd party | images | 200 | 906 ms | 33.6 KB |
| https://gdx-assets.costco.com/adobe/assets/urn%3Aaaid%3Aaem%3A7707a17d-6699-419d-a4fc-51bdbc664b50/as/26w05292_hp_icon_while_supplies_last.avif?width=320 3rd party | images | 200 | 904 ms | 35.5 KB |
| https://gdx-assets.costco.com/adobe/assets/urn%3Aaaid%3Aaem%3A2d722092-1c34-4f57-bd59-d90ded59aa45/as/26w05292_hp_icon_grocery.avif?width=320 3rd party | images | 200 | 899 ms | 25.1 KB |
| https://gdx-assets.costco.com/adobe/assets/urn%3Aaaid%3Aaem%3A6e8cb054-f51a-475f-b28a-4204dc015a77/as/26w05292_hp_icon_whats_new.avif?width=320 3rd party | images | 200 | 893 ms | 18.4 KB |
| https://gdx-assets.costco.com/adobe/assets/urn:aaid:aem:700b4244-1830-4bb4-8c15-89ec75777531/as/Costco-logo-HEX.avif?width=320 3rd party | images | 200 | 892 ms | 27.5 KB |
| https://gdx-assets.costco.com/adobe/assets/urn%3Aaaid%3Aaem%3A608629bc-6109-47e1-9606-9d3d052e9b37/as/transparent_banner_8x.avif?width=320 3rd party | images | 200 | 886 ms | 110 B |
| https://gdx-assets.costco.com/adobe/assets/urn:aaid:aem:b5d095a0-a857-443d-80ea-61d4e5d983f6/as/26w05292_hp_icon_mvm.avif 3rd party | images | 200 | 884 ms | 26.6 KB |
| https://gdx-assets.costco.com/adobe/assets/urn:aaid:aem:6c33d3d3-0b73-40e1-b59f-fd468411ebf1/as/27w511250_top_50_deals_cornerstone.avif?width=320 3rd party | images | 200 | 875 ms | 17.7 KB |
| https://gdx-assets.costco.com/adobe/assets/urn:aaid:aem:b5d095a0-a857-443d-80ea-61d4e5d983f6/as/26w05292_hp_icon_mvm.avif?width=320 3rd party | images | 200 | 873 ms | 26.8 KB |
| https://gdx-assets.costco.com/adobe/assets/urn:aaid:aem:48f1f1b9-89ab-4280-bdbe-163ae328b952/as/d_27w460623_banner_nov_mvm.avif 3rd party | images | 200 | 867 ms | 70.1 KB |
| https://gdx-assets.costco.com/adobe/assets/urn%3Aaaid%3Aaem%3A4c0e7b4c-1cf8-4f38-8f92-a9a0da781b2d/as/26w05292_hp_icon_this_week.avif 3rd party | images | 200 | 862 ms | 54.8 KB |
| https://gdx-assets.costco.com/adobe/assets/urn:aaid:aem:6c33d3d3-0b73-40e1-b59f-fd468411ebf1/as/27w511250_top_50_deals_cornerstone.avif 3rd party | images | 200 | 859 ms | 14.8 KB |
| https://gdx-assets.costco.com/adobe/assets/urn%3Aaaid%3Aaem%3Af45b3844-c2c8-4df6-bd4c-837cdaa44cc0/as/26w05292_hp_icon_treasure_hunt.avif 3rd party | images | 200 | 850 ms | 28.3 KB |
| https://gdx-assets.costco.com/adobe/assets/urn%3Aaaid%3Aaem%3A608629bc-6109-47e1-9606-9d3d052e9b37/as/transparent_banner_8x.avif 3rd party | images | 200 | 844 ms | 118 B |
| https://gdx-assets.costco.com/adobe/assets/urn%3Aaaid%3Aaem%3A7707a17d-6699-419d-a4fc-51bdbc664b50/as/26w05292_hp_icon_while_supplies_last.avif 3rd party | images | 200 | 841 ms | 52.2 KB |
| https://gdx-assets.costco.com/adobe/assets/urn%3Aaaid%3Aaem%3A2d722092-1c34-4f57-bd59-d90ded59aa45/as/26w05292_hp_icon_grocery.avif 3rd party | images | 200 | 839 ms | 37.5 KB |
| https://gdx-assets.costco.com/adobe/assets/urn%3Aaaid%3Aaem%3A6e8cb054-f51a-475f-b28a-4204dc015a77/as/26w05292_hp_icon_whats_new.avif 3rd party | images | 200 | 835 ms | 20.6 KB |
| https://gdx-assets.costco.com/adobe/assets/urn%3Aaaid%3Aaem%3A44822626-7e58-47df-b18c-b46f76dbc506/as/26w10169_hp_icon_services.avif 3rd party | images | 200 | 823 ms | 27.7 KB |
| https://gdx-assets.costco.com/adobe/assets/urn%3Aaaid%3Aaem%3A2bf6a432-5e6d-4d70-9433-702565ddbb36/as/26w05292_hp_icon_new_lower_prices.avif 3rd party | images | 200 | 821 ms | 13.0 KB |
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