www.klaviyo.com speed test — 20 Oct 2026

Measured from the wfix.shop server on 20 October 2026 at 12:25 UTC. Grade B (84/100), with the screenshots, the timings and the fixes that matter.

https://www.klaviyo.com/

20 October 2026 at 12:25 UTC · Free test · report pt_7360941319c7
Grade
B
84/100
Performance93/100
Structure71/100

11 audit(s) passed, 5 need work

First byte (TTFB)208 msmeasured from this server
Fully loaded1.87 sfirst byte + slowest asset
Requests26document + assets
Page weight1.52 MBcompressed transfer
HTML document71.9 KBgzip
ProtocolHTTP/3cloudflare
Third-party1.45 MBother hosts

Where the first byte went

  • DNS lookup 39 ms 19%
  • TCP connect 2 ms 1%
  • Server wait 167 ms 80%

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

First bytefaster than 91% of 4,999 pages tested here208 ms against a median of 449 ms
Page weightheavier than 74% of 4,999 pages tested here1.52 MB against a median of 650.3 KB
Fully loadedslower than 51% of 4,999 pages tested here1.87 s against a median of 1.84 s
Requestssends more requests than 100% of 4,999 pages tested here26 against a median of 26

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 208 ms. That is workable, and the cheapest win left is caching or a warmer connection.
  • The page transfers 1.52 MB over 26 request(s). Images files are 95% 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.
  • 95% 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 1.57 s, inside the 2.5 s Google calls good.
  • Layout stayed still (CLS 0.057), so nothing jumps under the reader's cursor.
  • The main thread was blocked for 663 ms, so taps and scrolling wait while scripts run.

Fix first: Image delivery and format - Serve WebP or AVIF with a JPEG fallback, size images to the space they occupy, and lazy-load anything below the fold. Images are usually more than half of a slow page.

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.

Mobile screenshot of www.klaviyo.com
Mobile 390 × 844 · 47.7 KB · page is 6000 px tall

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.

Largest contentful paint1.57 sgood is under 2.5 s
Cumulative layout shift0.057under 0.1 is stable
Total blocking time663 mslong tasks during load
First contentful paint1.57 sfirst content on screen
Browser page weight8.09 MB441 request(s), scripts included
Failed requests30blocked or unreachable
Largest contentful paint1.57 s
Goodgood under 2.5 s, poor over 4 s
Cumulative layout shift0.057
Goodgood under 0.1, poor over 0.25
Total blocking time663 ms
Poorgood under 200 ms, poor over 600 ms

Page weight by type

What the page is made of

Images 25 requests
1.45 MB 95%

Transfer size, compressed as sent. 26 request(s) in total, 1.52 MB across all of them.

Top issues

Image delivery and format

high impact

4 image(s) over 200 KB and 2 large image(s) still served as JPEG or PNG.

Fix: Serve WebP or AVIF with a JPEG fallback, size images to the space they occupy, and lazy-load anything below the fold. Images are usually more than half of a slow page.

Render-blocking resources

high impact

13 render-blocking resource(s) in the document head (7 script(s), 6 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 impact

The page transfers 1.52 MB across 26 request(s), with the document itself at 71.9 KB.

Fix: Work through the heaviest assets first: images, then fonts, then third-party scripts.

Third-party weight

medium impact

1 third-party host(s) serve 1.45 MB 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.

Avoid extra redirects

medium impact

1 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

IMAGEScdn.sanity.io/images/6ct6b26e/marketing-prod/e5b52b9…
1.66 s
IMAGEScdn.sanity.io/images/6ct6b26e/marketing-prod/1729491…
1.45 s
IMAGEScdn.sanity.io/images/6ct6b26e/marketing-prod/c5f5485…
1.45 s
IMAGEScdn.sanity.io/images/6ct6b26e/marketing-prod/323a5f9…
1.45 s
IMAGEScdn.sanity.io/images/6ct6b26e/marketing-prod/9c5d6de…
1.44 s
IMAGEScdn.sanity.io/images/6ct6b26e/marketing-prod/284f8f3…
1.44 s
IMAGEScdn.sanity.io/images/6ct6b26e/marketing-prod/109a350…
1.43 s
IMAGEScdn.sanity.io/images/6ct6b26e/marketing-prod/c02ae52…
1.43 s
IMAGEScdn.sanity.io/images/6ct6b26e/marketing-prod/ca54799…
1.43 s
IMAGEScdn.sanity.io/images/6ct6b26e/marketing-prod/c08e85f…
1.43 s

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

RequestTypeStatusTimeSize
https://cdn.sanity.io/images/6ct6b26e/marketing-prod/e5b52b9391bd946c76be89c4b589308de523a908-109x36.svg 3rd partyimages2001.66 s3.6 KB
https://cdn.sanity.io/images/6ct6b26e/marketing-prod/172949181a096ddede13ff947dacd3e32d0d04f3-74x25.svg 3rd partyimages2001.45 s1.9 KB
https://cdn.sanity.io/images/6ct6b26e/marketing-prod/c5f548551ca0d2f5179607aa8c60c530a474188a-62x25.svg 3rd partyimages2001.45 s2.1 KB
https://cdn.sanity.io/images/6ct6b26e/marketing-prod/323a5f9b46cbe3830fb123d1c0d93370579822e6-76x25.svg 3rd partyimages2001.45 s546 B
https://cdn.sanity.io/images/6ct6b26e/marketing-prod/9c5d6de9f822f854126a2d7734ae5ce0da83c9cd-174x25.svg 3rd partyimages2001.44 s4.1 KB
https://cdn.sanity.io/images/6ct6b26e/marketing-prod/284f8f376870cc72c3930886999d4a7032e4704d-80x25.svg 3rd partyimages2001.44 s1.8 KB
https://cdn.sanity.io/images/6ct6b26e/marketing-prod/109a3506d4123b3039bcd2796e0871171933dcf7-47x27.svg 3rd partyimages2001.43 s5.3 KB
https://cdn.sanity.io/images/6ct6b26e/marketing-prod/c02ae52e75c01ec6d9b78d75932a27ecb82adbf0-165x20.svg 3rd partyimages2001.43 s2.4 KB
https://cdn.sanity.io/images/6ct6b26e/marketing-prod/ca5479952c2f55047fec0cf71fa9fd64bb0480d9-59x25.svg 3rd partyimages2001.43 s1.1 KB
https://cdn.sanity.io/images/6ct6b26e/marketing-prod/c08e85faec7b475ca41456911264dbd29cd01a71-75x25.svg 3rd partyimages2001.43 s3.4 KB
https://cdn.sanity.io/images/6ct6b26e/marketing-prod/8ccdbfd6875f2a9ea842d2a444b557a86d8b061b-158x25.svg 3rd partyimages2001.42 s2.3 KB
https://cdn.sanity.io/images/6ct6b26e/marketing-prod/cbe11091b91c8f140bf47b6656218b19b0bd9fac-262x120.webp 3rd partyimages2001.40 s2.0 KB
https://cdn.sanity.io/images/6ct6b26e/marketing-prod/ebac5b0bbbfad81c1d7784c51c525832e7700a38-262x120.webp 3rd partyimages2001.39 s1.6 KB
https://cdn.sanity.io/images/6ct6b26e/marketing-prod/1a5c39e138782b1c78ca3b31777165ec83578759-2560x1440.png 3rd partyimages2001.39 s716.6 KB
https://cdn.sanity.io/images/6ct6b26e/marketing-prod/ce5b07ba71d2f4ad7dda0ced439c6b20c954e263-669x400.webp 3rd partyimages2001.39 s217.6 KB
https://cdn.sanity.io/images/6ct6b26e/marketing-prod/240f336acd9c9d6c0a85dcd83e7d8bf4aa52a242-668x400.png 3rd partyimages2001.39 s7.4 KB
https://cdn.sanity.io/images/6ct6b26e/marketing-prod/e2f45c0fc5f966c785dbcb07deb943a8881a3ed7-668x400.png 3rd partyimages2001.38 s7.5 KB
https://cdn.sanity.io/images/6ct6b26e/marketing-prod/baeb51700705ac37ed422f09fff04a0bf9900422-668x400.webp 3rd partyimages2001.38 s274.2 KB
https://cdn.sanity.io/images/6ct6b26e/marketing-prod/a25b012605e70029af45f9635faa838fe4a02937-262x120.png 3rd partyimages2001.37 s3.3 KB
https://cdn.sanity.io/images/6ct6b26e/marketing-prod/ea92879e13620ad4c849c1d0322334fb409ed111-262x120.webp 3rd partyimages2001.37 s1.9 KB
https://cdn.sanity.io/images/6ct6b26e/marketing-prod/14dd82bd9290f44c61170a0dc03897f35a3481e1-2112x1944.png 3rd partyimages2001.36 s202.1 KB
https://cdn.sanity.io/images/6ct6b26e/marketing-prod/810a806fe9ab3d05f9e2bfc701aba0774b1866b5-262x120.webp 3rd partyimages2001.36 s11.9 KB
https://cdn.sanity.io/images/6ct6b26e/marketing-prod/c6ed1df15110637c62d39aa02b6da60157a57abc-262x120.png 3rd partyimages2001.36 s2.6 KB
https://cdn.sanity.io/images/6ct6b26e/marketing-prod/7c3c7232e4d426b133fb7a1458ee5a6faa371eaf-262x120.webp 3rd partyimages2001.36 s2.1 KB
https://cdn.sanity.io/images/6ct6b26e/marketing-prod/43f28b304c058503374e25edfb214b7eed123afc-262x120.webp 3rd partyimages2001.36 s1.8 KB
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