Performance

· 27 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.

SCORE

GRADE

FIX

REVIEW

PASS

INFO

Performance-focused optimization plan with CWV assessment, top offenders, and time estimates

Mobile Desktop

Performance

Accessibility

Best Practices

SEO

First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.

3.47 s

Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.

9.40 s

Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.

3.51 s

Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.

0.005

Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.

9.43 s

Time to Interactive Time to Interactive — how long until the page is fully interactive and responds to user input. Under 3.8s is good.

32.01 s

Page Load Progression

853 ms

1.7 s

2.6 s

3.4 s

4.3 s

5.1 s

6.0 s

6.8 s

Checks

12 PASS 5 REVIEW 6 FIX

Page Weight Budget

Action

4.8 MB transferred, 343 requests

FIX

4.8 MB transferred, 343 requests

Page weighs 12.8 MB (4.8 MB transferred)

JavaScript is 2.5 MB — consider code splitting or lazy loading

Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.

Got: 2.5 MB

Fonts are 491 KB — consider subsetting or using system fonts

Subset fonts to include only used characters, or switch to system font stacks.

Got: 491 KB

343 HTTP requests — consider bundling or reducing

Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.

Estimated 1.00 g CO2 per page load

4.8 MB transferred

343 requests

1.00 g CO2 per page load

JavaScript 2.5 MiB 52%

Other 946.0 KiB 19%

Images 698.7 KiB 14%

Fonts 491.5 KiB 10%

HTML 94.8 KiB 2%

Other 57.0 KiB 1%

CSS 42.6 KiB 1%

Other 14.1 KiB 0%

Other 10.0 KiB 0%

Other 0 B 0%

0 2.4 MB 4.9 MB

Over budget

Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.

Why this matters

JavaScript bundle is large — code-split routes and lazy-load off-screen components to defer.

Source: web.dev

Subset fonts to include only used characters, or switch to system font stacks.

Why this matters

Font payload is large — subset to used glyphs only, or fall back to system fonts (zero load time).

Source: web.dev font loading

Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.

Why this matters

High HTTP request count — bundling, sprite-ing, and HTTP/2 server push can reduce per-request overhead.

Source: web.dev

Third-Party Impact

Action

100% third-party, 0 ms blocking

FIX

100% third-party, 0 ms blocking

Third-party code accounts for 100% of page weight (4.7 MiB of 4.8 MiB)

Third-party blocking time is low (0 ms)

100%

First-party Third-party

JS Execution Cost

Action

14262ms total JS execution

FIX

14262ms total JS execution

https://1click-blinds.com/?shpxid=58ed8335-67be-43...: 4302ms CPU time

Unattributable: 2731ms CPU time

https://1click-blinds.com/cdn/wpm/b5f5c0921we198f8...: 1323ms CPU time

https://1click-blinds.com/cdn/shop/t/30/assets/laz...: 698ms CPU time

https://connect.facebook.net/en_US/fbevents.js: 660ms CPU time

Third-party scripts: 11531ms (81% of total)

Main Thread Breakdown

Script Evaluation 43% Other 28% Style & Layout 11% Script Parsing & Compilation 8% Rendering 7%

Script	Total	Scripting	Parse/Compile	Party
https://1click-blinds.com/?shpxid=58ed8335-67be-4353-b58c-1e77648bb971	4302ms	354ms	80ms	3rd
Unattributable	2731ms	305ms	0ms	1st
https://1click-blinds.com/cdn/wpm/b5f5c0921we198f819p6efddfcfm66c0f9a3m.js	1323ms	1065ms	27ms	3rd
https://1click-blinds.com/cdn/shop/t/30/assets/lazysizes.js?v=9525017869278013171786454101	698ms	325ms	2ms	3rd
https://connect.facebook.net/en_US/fbevents.js	660ms	424ms	60ms	3rd
https://www.googletagmanager.com/gtag/js?id=GT-K55FGPL	432ms	365ms	64ms	3rd
https://www.googletagmanager.com/gtag/js?id=G-NWS4WBSBS1	424ms	346ms	75ms	3rd
https://assets.cloudlift.app/api/assets/options.js?shop=831ba5-4.myshopify.com	417ms	128ms	246ms	3rd
https://cdn.shopify.com/storefront/web-components/agent.js	356ms	333ms	0ms	3rd
https://js.klarna.com/web-sdk/v1/1.0.238/sdk.js	346ms	252ms	3ms	3rd

Showing top 10 of 29 scripts

JS Bundles

Action

212 scripts, 732 KB unused

FIX

212 scripts, 732 KB unused

https://cdn.jsdelivr.net/gh/cloudlift-app/cdn@0.15...: 128 KB unused (92%)

Consider code splitting or tree shaking to reduce unused code.

https://www.googletagmanager.com/gtag/js?id=G-NWS4...: 122 KB unused (67%)

Consider code splitting or tree shaking to reduce unused code.

https://cdnjs.cloudflare.com/ajax/libs/three.js/r1...: 86 KB unused (73%)

Consider code splitting or tree shaking to reduce unused code.

https://js.klarna.com/web-sdk/v1/1.0.238/sdk.js: 78 KB unused (53%)

Consider code splitting or tree shaking to reduce unused code.

https://www.googletagmanager.com/gtag/js?id=G-NWS4...: 75 KB unused (41%)

Consider code splitting or tree shaking to reduce unused code.

Total unused JavaScript: 732 KB

732 KB unused JavaScript

Downloaded but never executed on this page.

Script	Size	Unused	Minified	Party
https://cdn.jsdelivr.net/gh/cloudlift-app/cdn@0.15.68/static/app-options.js	140 KB	128 KB (92%)	✓	3rd
https://www.googletagmanager.com/gtag/js?id=G-NWS4WBSBS1&cx=c&gtm=4e68h0h2	182 KB	122 KB (67%)	✓	3rd
https://cdnjs.cloudflare.com/ajax/libs/three.js/r128/three.min.js	119 KB	86 KB (73%)	✓	3rd
https://js.klarna.com/web-sdk/v1/1.0.238/sdk.js	146 KB	78 KB (53%)	✓	3rd
https://www.googletagmanager.com/gtag/js?id=G-NWS4WBSBS1	182 KB	75 KB (41%)	✓	3rd
https://www.googletagmanager.com/gtag/js?id=GT-K55FGPL	144 KB	63 KB (44%)	✓	3rd
https://cdn.shopify.com/extensions/019f3d7a-6de3-7ebf-83ac-112375e26f04/product-samples-92/assets/main.min.js?shop=831ba5-4.myshopify.com	65 KB	42 KB (65%)	✓	3rd
https://connect.facebook.net/en_US/fbevents.js	105 KB	40 KB (38%)	✓	3rd
https://1click-blinds.com/cdn/shop/t/30/assets/swiper-bundle.min.js?v=118526235923544450021786454101	37 KB	35 KB (97%)	✓	3rd
https://cdn.shopify.com/extensions/01a01398-8859-762f-846a-c9ef2f347a9b/pushowl-320/assets/pushowl-shopify-main.js	56 KB	35 KB (62%)	✓	3rd

Consider code splitting or tree shaking to reduce unused code.

Why this matters

This bundle has high unused code — code-split or tree-shake to ship only what executes.

Source: web.dev / Lighthouse coverage

Consider code splitting or tree shaking to reduce unused code.

Why this matters

This bundle has high unused code — code-split or tree-shake to ship only what executes.

Source: web.dev / Lighthouse coverage

Consider code splitting or tree shaking to reduce unused code.

Why this matters

This bundle has high unused code — code-split or tree-shake to ship only what executes.

Source: web.dev / Lighthouse coverage

Consider code splitting or tree shaking to reduce unused code.

Why this matters

This bundle has high unused code — code-split or tree-shake to ship only what executes.

Source: web.dev / Lighthouse coverage

Consider code splitting or tree shaking to reduce unused code.

Why this matters

This bundle has high unused code — code-split or tree-shake to ship only what executes.

Source: web.dev / Lighthouse coverage

Page Weight Inventory

Action

343 resources · 4.8 MB · 732 KB savings available

FIX

343 resources · 4.8 MB · 732 KB savings available

Page weight 4.8 MB exceeds 1 MB target by 3.8 MB

Got: 4.8 MB Expected: ≤ 1 MB

~732 KB of savings available

342 third-party resources (100% of weight)

1 resources over 200KB

343 resources · 4.8 MiB · 342 third-party 3.8 MiB over 1MB target

JavaScript 71% · 3.4 MiB

Image 14% · 701.3 KiB

Font 10% · 491.5 KiB

Document 2% · 103.0 KiB

CSS 2% · 102.9 KiB

Other 1% · 28.6 KiB

~732.5 KiB of savings available

Remove unused JavaScript: 732.5 KiB

#	Resource	Type	Size	Cache	Unused	3rd party	Issues

343 resources			4.8 MiB

HTTP Caching

Action

No cache headers

FIX

No cache headers

No Cache-Control header found

Browsers will use heuristic caching, which can be unpredictable. Set explicit cache headers.

ETag present — enables conditional (304) responses

No Cache-Control header

Adding a Cache-Control header can significantly improve repeat-visit performance.

Image Optimization

Action

30 images, 0 KB saveable

REVIEW

30 images, 0 KB saveable

https://cdn.shopify.com/s/files/1/0795/7522/0570/f... is missing width/height — may cause layout shift

Set explicit width and height to prevent CLS.

https://cdn.shopify.com/s/files/1/0795/7522/0570/f... is missing width/height — may cause layout shift

Set explicit width and height to prevent CLS.

30 images 699 KB

0 oversized -0 KB

18 legacy format

2 missing dimensions CLS risk

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

Main HTML Cache-Control

No Cache-Control header on main HTML response

REVIEW

No Cache-Control header on main HTML response

Main HTML response has no Cache-Control header

Without an explicit Cache-Control, browsers fall back to heuristic caching (~10% of Last-Modified age). Set `Cache-Control: no-cache` or `max-age=300` for HTML to control freshness explicitly -- prevents stale auth state and SPA shell drift.

JavaScript Blocking

2 JS blocking issue(s) detected

REVIEW

2 JS blocking issue(s) detected

3 render-blocking <script src> tag(s) without async/defer

Each `<script src=...>` without `async`, `defer`, or `type="module"` blocks HTML parsing while the browser fetches and executes it. The block lasts the entire round-trip + execution time -- on slow networks this translates directly into LCP delay. Add `defer` (executes after parse, in source order) for scripts that interact with the DOM, or `async` (executes whenever ready) for analytics / independent scripts. Module scripts (`type="module"`) are deferred by default.

Total JS execution time is 14.3 s -- over the 3.5s budget

Total JavaScript execution (parse + compile + run) across all scripts exceeds 3.5 seconds. On low-end devices that becomes 7-15+ seconds and shows up directly in TBT and INP. Reduce by: tree-shaking unused dependencies, code-splitting (dynamic `import()`), removing or deferring third-party tracking, and replacing heavy frameworks where they're not needed.

CSS Performance Depth

2 CSS depth issue(s) detected

REVIEW

2 CSS depth issue(s) detected

9 render-blocking stylesheet(s) -- recommended: <=3

Each `<link rel="stylesheet">` without a non-blocking `media` attribute holds up the first paint. Browsers download all of them before painting any content. Consolidate into 1-2 critical-path stylesheets; defer non-critical CSS via `<link rel="stylesheet" media="print" onload="this.media='all'">` or via the loadCSS pattern; inline above-the-fold CSS in `<style>` to short-circuit the request entirely.

5 `@font-face` rule(s) without `font-display` -- causes FOIT

An `@font-face` rule without `font-display` causes Flash of Invisible Text (FOIT): the browser hides the styled text for up to 3 seconds while the custom font downloads, then either swaps to fallback (Chrome / Firefox) or stays invisible (older Safari). Add `font-display: swap` (shows fallback immediately, swaps in the custom font when ready) or `font-display: optional` (uses fallback if the font isn't ready in 100ms; never causes visible swap). Either eliminates FOIT outright.

Green Hosting

Action

Whether the site is served from green-energy infrastructure

REVIEW

Green Hosting

No green hosting detected

A+

Text Compression

All text resources are compressed

PASS

All text resources are compressed

All text resources are properly compressed.

A+

Font Loading

12 fonts (491 KB)

PASS

12 fonts (491 KB)

12 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

491 KB total

Render-blocking

of 12

Dominant font-display

swap

Most common across fonts

Font loading timeline

Transfer FOIT (block) FOUT (swap)

roboto_n3.9ac06d5955eb6... woff2 swap

Size 33 KB

Load time 39 ms

Start 428 ms

Risk FOUT — text flashes from fallback to web font

roboto_n4.2019d890f07b1... woff2 swap

Size 31 KB

Load time 31 ms

Start 429 ms

Risk FOUT — text flashes from fallback to web font

roboto_n5.250d51708d76a... woff2 swap

Size 34 KB

Load time 41 ms

Start 430 ms

Risk FOUT — text flashes from fallback to web font

roboto_n6.3d305d5382545... woff2 swap

Size 34 KB

Load time 45 ms

Start 430 ms

Risk FOUT — text flashes from fallback to web font

roboto_n7.f38007a10afbb... woff2 swap

Size 34 KB

Load time 34 ms

Start 430 ms

Risk FOUT — text flashes from fallback to web font

domine_n4.db7650f19fc58... woff2 swap

Size 22 KB

Load time 47 ms

Start 431 ms

Risk FOUT — text flashes from fallback to web font

domine_n5.68cd0419a0007... woff2 swap

Size 23 KB

Load time 54 ms

Start 431 ms

Risk FOUT — text flashes from fallback to web font

domine_n6.70313db433098... woff2 swap

Size 23 KB

Load time 51 ms

Start 432 ms

Risk FOUT — text flashes from fallback to web font

domine_n7.d520ceeab5a57... woff2 swap

Size 23 KB

Load time 60 ms

Start 432 ms

Risk FOUT — text flashes from fallback to web font

biotif.woff2 woff2 swap

Size 43 KB

Load time 96 ms

Start 845 ms

Risk FOUT — text flashes from fallback to web font

Biotif-Bold.woff2 woff2 swap

Size 46 KB

Load time 86 ms

Start 846 ms

Risk FOUT — text flashes from fallback to web font

fa-solid-900.woff2 woff2 swap

Size 147 KB

Load time 80 ms

Start 1.1 s

Risk FOUT — text flashes from fallback to web font

Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need

Optimization checklist

Preload critical fonts (priority=high)
Use woff2 format for all fonts
Set font-display to swap, optional, or fallback
Subset large fonts (≤100 KB each)

Fixing the unchecked items could save ~74 KB and ~148 ms

A+

Resource Caching

All resources properly cached

PASS

All resources properly cached

No caching issues found

All static resources have appropriate caching headers.

A+

Critical Rendering Path

No render-blocking resources

PASS

No render-blocking resources

No render-blocking resources detected

Resource Hints

20 hints, 0 missing preconnects

PASS

20 hints, 0 missing preconnects

9 font preload(s) missing `crossorigin` -- font will be downloaded twice

Fonts are always fetched as crossorigin=anonymous; a preload without the attribute creates a different cache key, so the browser refetches when the actual font request happens. Sample: //1click-blinds.com/cdn/fonts/roboto/roboto_n3.9ac06d5955eb603264929711f38e40623ddc14db.woff2, //1click-blinds.com/cdn/fonts/roboto/roboto_n4.2019d890f07b1852f56ce63ba45b2db45d852cba.woff2, //1click-blinds.com/cdn/fonts/roboto/roboto_n5.250d51708d76acbac296b0e21ede8f81de4e37aa.woff2 (+6 more). Add `crossorigin` (or `crossorigin="anonymous"`) to each preload.

Page uses 20 resource hint(s)

Current Resource Hints

preconnect

preload

dns-prefetch

prefetch

—

20 resource hints configured

Why this matters

Performance issues directly impact user engagement and conversion rates.

A+

HTTP/3 (QUIC)

HTTP/3 advertised via Alt-Svc

PASS

HTTP/3 advertised via Alt-Svc

HTTP/3 (QUIC) is supported

First-load mobile users on cellular networks see meaningful latency improvements with HTTP/3. The QUIC transport collapses TLS + TCP handshakes into one and recovers faster from packet loss.

A+

Compression Algorithm

Main response uses brotli

PASS

Main response uses brotli

Main HTML response uses brotli (Content-Encoding: br)

Brotli is the best text-compression algorithm for general use, ~20% smaller than gzip on average (40% on smaller files). Modern browsers all support it.

A+

LCP Image Preload

LCP preload audit not available

PASS

LCP preload audit not available

LCP image preload audit not available for this scan

A+

Server-Timing Observability

15 Server-Timing entries advertised

PASS

15 Server-Timing entries advertised

Server-Timing header advertises 15 timing entries

A+

Server Response Intelligence

2 server-response signal(s) detected

PASS

2 server-response signal(s) detected

`Vary` header declared: accept-encoding

The page declares a `Vary` header, telling downstream caches which request headers the response varies on. Critical for content-negotiated responses (compression, language, cookies, device class).

`ETag` present -- conditional GET supported

A+

Render-Blocking Resources

No render-blocking resources detected

PASS

No render-blocking resources detected

No render-blocking resources detected in <head>

A+

Third-Party Resources

No third-party resources detected

PASS

No third-party resources detected

Network Waterfall

343 requests over 6988ms

INFO

HTML JavaScript CSS Images Fonts XHR/Fetch Other

Third-Party Script Cost

Per-script blocking time, transfer cost, and cache headers

INFO

81% of JavaScript execution is third-party

First-party Third-party 11531ms · 1660KB · £60/mo

Script	Category	Execution	Transfer	Unused	Monthly Cost	Verdict
1click-blinds.com 1click-blinds.com	Other	4302ms	83 KB	—	£22/mo	Costly
1click-blinds.com 1click-blinds.com	Other	1323ms	71 KB	43%	£7/mo	Costly
1click-blinds.com 1click-blinds.com	Other	698ms	5 KB	—	£4/mo	Costly
Facebook Pixel connect.facebook.net	Advertising	660ms	105 KB	38%	£3/mo	Costly
Google Tag Manager www.googletagmanager.com	Tag Manager	432ms	144 KB	44%	£2/mo	Costly
Google Tag Manager www.googletagmanager.com	Tag Manager	424ms	182 KB	41%	£2/mo	Costly
assets.cloudlift.app assets.cloudlift.app	Other	417ms	187 KB	—	£2/mo	Costly
cdn.shopify.com cdn.shopify.com	Other	356ms	19 KB	—	£2/mo	Costly
js.klarna.com js.klarna.com	Other	346ms	146 KB	53%	£2/mo	Costly
1click-blinds.com 1click-blinds.com	Other	279ms	28 KB	—	£1/mo	Costly
1click-blinds.com 1click-blinds.com	Other	272ms	21 KB	—	£1/mo	Costly
product-samples.herokuapp.com product-samples.herokuapp.com	Other	272ms	0 KB	—	£1/mo	Costly
1click-blinds.com 1click-blinds.com	Other	258ms	23 KB	—	£1/mo	Costly
1click-blinds.com 1click-blinds.com	Other	152ms	1 KB	—	£1/mo	Optional
cdn.shopify.com cdn.shopify.com	Other	133ms	65 KB	65%	£1/mo	Optional
static.klaviyo.com static.klaviyo.com	Other	130ms	9 KB	—	£1/mo	Optional
jsDelivr cdn.jsdelivr.net	CDN	129ms	140 KB	92%	£1/mo	Optional
cdnjs cdnjs.cloudflare.com	CDN	125ms	119 KB	73%	£1/mo	Optional
code.jquery.com code.jquery.com	Other	107ms	30 KB	—	£1/mo	Optional
Facebook Pixel connect.facebook.net	Advertising	106ms	25 KB	—	£1/mo	Optional
Google Tag Manager www.googletagmanager.com	Tag Manager	102ms	182 KB	67%	£1/mo	Optional
sdks.automizely.com sdks.automizely.com	Other	92ms	18 KB	—	£0/mo	Optional
js.klarna.com js.klarna.com	Other	80ms	24 KB	—	£0/mo	Optional
1click-blinds.com 1click-blinds.com	Other	80ms	4 KB	—	£0/mo	Optional
1click-blinds.com 1click-blinds.com	Other	76ms	4 KB	—	£0/mo	Optional
1click-blinds.com 1click-blinds.com	Other	69ms	0 KB	—	£0/mo	Optional
cdn-v2.reelup.io cdn-v2.reelup.io	Other	57ms	9 KB	—	£0/mo	Optional
static-tracking.klaviyo.com static-tracking.klaviyo.com	Other	53ms	14 KB	—	£0/mo	Optional

1click-blinds.com

Other

Costly

Execution 4302ms

Transfer 83 KB

Monthly Cost £22/mo

1click-blinds.com

Other

Costly

Execution 1323ms

Transfer 71 KB

Unused 43%

Monthly Cost £7/mo

1click-blinds.com

Other

Costly

Execution 698ms

Transfer 5 KB

Monthly Cost £4/mo

Facebook Pixel

Advertising

Costly

Execution 660ms

Transfer 105 KB

Unused 38%

Monthly Cost £3/mo

Google Tag Manager

Tag Manager

Costly

Execution 432ms

Transfer 144 KB

Unused 44%

Monthly Cost £2/mo

Google Tag Manager

Tag Manager

Costly

Execution 424ms

Transfer 182 KB

Unused 41%

Monthly Cost £2/mo

assets.cloudlift.app

Other

Costly

Execution 417ms

Transfer 187 KB

Monthly Cost £2/mo

cdn.shopify.com

Other

Costly

Execution 356ms

Transfer 19 KB

Monthly Cost £2/mo

js.klarna.com

Other

Costly

Execution 346ms

Transfer 146 KB

Unused 53%

Monthly Cost £2/mo

1click-blinds.com

Other

Costly

Execution 279ms

Transfer 28 KB

Monthly Cost £1/mo

1click-blinds.com

Other

Costly

Execution 272ms

Transfer 21 KB

Monthly Cost £1/mo

product-samples.herokuapp.com

Other

Costly

Execution 272ms

Transfer 0 KB

Monthly Cost £1/mo

1click-blinds.com

Other

Costly

Execution 258ms

Transfer 23 KB

Monthly Cost £1/mo

1click-blinds.com

Other

Optional

Execution 152ms

Transfer 1 KB

Monthly Cost £1/mo

cdn.shopify.com

Other

Optional

Execution 133ms

Transfer 65 KB

Unused 65%

Monthly Cost £1/mo

static.klaviyo.com

Other

Optional

Execution 130ms

Transfer 9 KB

Monthly Cost £1/mo

jsDelivr

CDN

Optional

Execution 129ms

Transfer 140 KB

Unused 92%

Monthly Cost £1/mo

cdnjs

CDN

Optional

Execution 125ms

Transfer 119 KB

Unused 73%

Monthly Cost £1/mo

code.jquery.com

Other

Optional

Execution 107ms

Transfer 30 KB

Monthly Cost £1/mo

Facebook Pixel

Advertising

Optional

Execution 106ms

Transfer 25 KB

Monthly Cost £1/mo

Google Tag Manager

Tag Manager

Optional

Execution 102ms

Transfer 182 KB

Unused 67%

Monthly Cost £1/mo

sdks.automizely.com

Other

Optional

Execution 92ms

Transfer 18 KB

Monthly Cost £0/mo

js.klarna.com

Other

Optional

Execution 80ms

Transfer 24 KB

Monthly Cost £0/mo

1click-blinds.com

Other

Optional

Execution 80ms

Transfer 4 KB

Monthly Cost £0/mo

1click-blinds.com

Other

Optional

Execution 76ms

Transfer 4 KB

Monthly Cost £0/mo

1click-blinds.com

Other

Optional

Execution 69ms

Transfer 0 KB

Monthly Cost £0/mo

cdn-v2.reelup.io

Other

Optional

Execution 57ms

Transfer 9 KB

Monthly Cost £0/mo

static-tracking.klaviyo.com

Other

Optional

Execution 53ms

Transfer 14 KB

Monthly Cost £0/mo

These scripts may cost more than they're worth

1click-blinds.com adds 4302ms and costs ~£22/month
1click-blinds.com adds 1323ms and costs ~£7/month
1click-blinds.com adds 698ms and costs ~£4/month
Facebook Pixel adds 660ms and costs ~£3/month
Google Tag Manager adds 432ms and costs ~£2/month
Google Tag Manager adds 424ms and costs ~£2/month
assets.cloudlift.app adds 417ms and costs ~£2/month
cdn.shopify.com adds 356ms and costs ~£2/month
js.klarna.com adds 346ms and costs ~£2/month
1click-blinds.com adds 279ms and costs ~£1/month
1click-blinds.com adds 272ms and costs ~£1/month
product-samples.herokuapp.com adds 272ms and costs ~£1/month
1click-blinds.com adds 258ms and costs ~£1/month

81% of JavaScript execution time is spent on third-party scripts. Consider auditing which scripts are essential.

Why this matters

When third-party JS execution time exceeds your own, performance gains from frontend work are capped by code you don't own.

Learn more ▾

Every millisecond of third-party JS competes with your own for main-thread time. If their share is bigger than yours, optimization on your code base barely moves the needle. Audit, defer, or remove third-parties before further frontend optimization. Use Lighthouse's third-party audit to identify the worst offenders.

Source: web.dev

1click-blinds.com takes 4302ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

1click-blinds.com takes 1323ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

1click-blinds.com takes 698ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

Facebook Pixel takes 660ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

Google Tag Manager takes 432ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

Google Tag Manager takes 424ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

assets.cloudlift.app takes 417ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

cdn.shopify.com takes 356ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

js.klarna.com takes 346ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

53% of js.klarna.com's code is unused. The script may be loading features you don't use.

Why this matters

Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.

Source: web.dev

1click-blinds.com takes 279ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

1click-blinds.com takes 272ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

product-samples.herokuapp.com takes 272ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

1click-blinds.com takes 258ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

65% of cdn.shopify.com's code is unused. The script may be loading features you don't use.

Why this matters

Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.

Source: web.dev

92% of jsDelivr's code is unused. The script may be loading features you don't use.

Why this matters

Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.

Source: web.dev

73% of cdnjs's code is unused. The script may be loading features you don't use.

Why this matters

Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.

Source: web.dev

67% of Google Tag Manager's code is unused. The script may be loading features you don't use.

Why this matters

Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.

Source: web.dev

How third-party costs are calculated

Real-User Performance (CrUX)

Field metrics from the Chrome User Experience Report

INFO

Chrome User Experience (CrUX)

Real-user metrics from the Chrome UX Report (2026-07-20 — 2026-08-16)

LCP (p75)

1631 ms

88% good

INP (p75)

94 ms

96% good

CLS (p75)

0.120

73% good

FCP (p75)

1423 ms

TTFB (p75)

397 ms

Image Optimization

20 images, 115 KB total, 85 KB wasted

INFO

Image Optimization Audit

Total Images

Total Size

115 KB

Oversized

Wasted

85 KB

5 missing alt text 18 missing dimensions 14 missing lazy loading

All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.