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https://simon.com

Performance

· 17 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
85
GRADE
B
FIX
3
REVIEW
3
PASS
9
INFO
2

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

Mobile Desktop
59
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
84
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
81
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
100
SEO Measures basic SEO optimizations: meta tags, crawlability, link text, and mobile friendliness.

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

1.97 s

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

4.22 s

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

1.34 s

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

0.000

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

3.44 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.

6.68 s

Page Load Progression

375 ms
750 ms
1.1 s
1.5 s
1.9 s
2.2 s
2.6 s
3.0 s
Checks
17
9 PASS 3 REVIEW 3 FIX
D
Third-Party Impact
Action
100% third-party, 0 ms blocking
FIX
100% third-party, 0 ms blocking
Warning::
Third-party code accounts for 100% of page weight (522.8 KiB of 522.9 KiB)
Info::
Third-party blocking time is low (0 ms)
100%
First-party Third-party
F
JS Execution Cost
Action
4084ms total JS execution
FIX
4084ms total JS execution
Warning::
https://www.simon.com/46SCNLxs/init.js: 2275ms CPU time
Warning::
https://www.simon.com/46SCNLxs/captcha/captcha.js?...: 1465ms CPU time
Warning::
Unattributable: 260ms CPU time
Info::
https://www.simon.com/: 84ms CPU time
Warning::
Third-party scripts: 4084ms (100% of total)

Main Thread Breakdown

Script Evaluation 67% Style & Layout 20% Other 8%
ScriptTotalScriptingParse/CompileParty
https://www.simon.com/46SCNLxs/init.js2275ms1432ms22ms3rd
https://www.simon.com/46SCNLxs/captcha/captcha.js?a=c&u=ca322762-3ea3-11f1-b019-a0f1c129ed94&v=&m=0&h=R0VU1465ms1313ms50ms3rd
Unattributable260ms7ms0ms3rd
https://www.simon.com/84ms6ms2ms3rd
F
HTTP Caching
Action
No cache headers
FIX
No cache headers
Warning::
No Cache-Control header found
Browsers will use heuristic caching, which can be unpredictable. Set explicit cache headers.

No Cache-Control header

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

C
JS Bundles
Action
8 scripts, 222 KB unused
REVIEW
8 scripts, 222 KB unused
Warning::
https://www.simon.com/46SCNLxs/init.js: 64 KB unused (44%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.simon.com/46SCNLxs/init.js: 64 KB unused (44%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.simon.com/46SCNLxs/captcha/captcha.js?...: 46 KB unused (18%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.simon.com/46SCNLxs/captcha/captcha.js?...: 46 KB unused (18%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 222 KB
222 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.simon.com/46SCNLxs/init.js154 KB64 KB (44%)✓3rd
https://www.simon.com/46SCNLxs/init.js7 KB64 KB (44%)✓3rd
https://www.simon.com/46SCNLxs/captcha/captcha.js?a=c&u=ca322762-3ea3-11f1-b019-a0f1c129ed94&v=&m=0&h=R0VU271 KB46 KB (18%)✓3rd
https://www.simon.com/46SCNLxs/captcha/captcha.js?a=c&u=ca322762-3ea3-11f1-b019-a0f1c129ed94&v=&m=0&h=R0VU0 KB46 KB (18%)✓3rd
https://www.simon.com/humanchallengepage.js8 KB—✓3rd
blob:https://www.simon.com/99ac2274-1e45-4374-8584-d954ba0715c30 KB—✓3rd
blob:https://www.simon.com/811c2e65-af28-4e3f-b81f-a7cc1ea007ec-0 KB—✓3rd
blob:https://www.simon.com/e192bcdd-ad2c-4734-97a4-3870cae546a6-0 KB—✓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

B
Page Weight Inventory
20 resources · 523 KB · 222 KB savings available
REVIEW
20 resources · 523 KB · 222 KB savings available
Info::
Within 1MB page-weight target
Got: 523 KB
Info::
~222 KB of savings available
Warning::
19 third-party resources (100% of weight)
Info::
1 resources over 200KB
20 resources · 522.9 KiB · 19 third-party Within 1MB page-weight target
JavaScript 84% · 440.7 KiB
Font 7% · 36.7 KiB
Image 5% · 25.8 KiB
Document 3% · 13.5 KiB
Other 1% · 3.3 KiB
CSS 1% · 2.9 KiB

~221.6 KiB of savings available

Remove unused JavaScript: 221.6 KiB
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A+
Page Weight Budget
523 KB transferred, 20 requests
PASS
523 KB transferred, 20 requests
Info::
Page weighs 1.1 MB (523 KB transferred)
Info::
20 HTTP requests
Info::
Estimated 0.11 g CO2 per page load
523 KB / 2.4 MB budget
523 KB transferred
20 requests
0.11 g CO2 per page load
JavaScript 433.3 KiB 83%
Fonts 36.7 KiB 7%
Images 15.8 KiB 3%
HTML 13.1 KiB 3%
Other 11.9 KiB 2%
Other 9.1 KiB 2%
CSS 2.9 KiB 1%
0 2.4 MB 4.9 MB
Under budget
A+
Text Compression
All text resources are compressed
PASS
All text resources are compressed
Info::
All text resources are compressed
All text resources are properly compressed.
A+
Image Optimization
1 images, 0 KB saveable
PASS
1 images, 0 KB saveable
Warning::
https://assets.simon.com/content/web/logos/Simon-L... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
1 images 16 KB
0 oversized -0 KB
0 legacy format
1 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

A+
Font Loading
2 fonts (37 KB)
PASS
2 fonts (37 KB)
Info::
2 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

2

37 KB total

Render-blocking

0

of 2

Dominant font-display

swap

Most common across fonts

Font loading timeline
Transfer FOIT (block) FOUT (swap)
0 ms 1.0 s 2.0 s 3.0 s 4.0 s FCP 2.0 s LCP 4.2 shttps://fonts.gstatic.com/s/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3yUBHMdazQ.woff2KFO7CnqEu92Fr1ME7kSn66a... https://fonts.gstatic.com/s/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3yUBHMdazQ.woff2 — 36.7 KiB — 67 ms — font-display: swaphttps://fonts.gstatic.com/s/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3yUBHMdazQ.woff2KFO7CnqEu92Fr1ME7kSn66a... https://fonts.gstatic.com/s/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3yUBHMdazQ.woff2 — 0 B — 0 ms — font-display: swap
KFO7CnqEu92Fr1ME7kSn66a... woff2 swap
Size 37 KB
Load time 67 ms
Start 950 ms
Risk FOUT — text flashes from fallback to web font
KFO7CnqEu92Fr1ME7kSn66a... woff2 swap
Size 0 KB
Load time 0 ms
Start 1.2 s
Risk FOUT — text flashes from fallback to web font
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)
A+
Resource Caching
All resources properly cached
PASS
All resources properly cached
Info::
No caching issues found
All static resources have appropriate caching headers.
A+
Critical Rendering Path
No render-blocking resources
PASS
No render-blocking resources
Info::
No render-blocking resources detected
A+
Resource Hints
No optimization needed
PASS
No optimization needed
Info::
No resource hint issues
A+
Render-Blocking Resources
No render-blocking resources detected
PASS
No render-blocking resources detected
Info::
No render-blocking resources detected in <head>
A+
Third-Party Resources
No third-party resources detected
PASS
No third-party resources detected
Network Waterfall
20 requests over 2662ms
INFO
0 ms 1.0 s 2.0 s 3.0 s 4.0 s FCP 2.0 s LCP 4.2 shttps://simon.com// https://simon.com/ — 301 — 100 B — 298 ms — h2https://www.simon.com/www.simon.com/ https://www.simon.com/ — 307 — 13.1 KiB — 135 ms — h2https://www.simon.com/humanchallengepage.jswww.simon.com/humanchallengepage.js https://www.simon.com/humanchallengepage.js — 200 — 7.9 KiB — 3 ms — h2https://www.simon.com/46SCNLxs/captcha/captcha.js?a=c&u=ca322762-3ea3-11f1-b019-a0f1c129ed94&v=&m=0&h=R0VUwww.simon.com/46SCNLxs/captcha/capt... https://www.simon.com/46SCNLxs/captcha/captcha.js?a=c&u=ca322762-3ea3-11f1-b019-a0f1c129ed94&v=&m=0&h=R0VU — 200 — 271.4 KiB — 158 ms — h2https://fonts.googleapis.com/css2?family=Roboto:ital,wght@0,100;0,300;0,400;0,500;0,700;0,900;1,100;1,300;1,400;1,500;1,700;1,900&display=swapfonts.googleapis.com/css2?family=Ro... https://fonts.googleapis.com/css2?family=Roboto:ital,wght@0,100;0,300;0,400;0,500;0,700;0,900;1,100;1,300;1,400;1,500;1,700;1,900&display=swap — 200 — 2.9 KiB — 114 ms — h2https://www.simon.com/46SCNLxs/init.jswww.simon.com/46SCNLxs/init.js https://www.simon.com/46SCNLxs/init.js — 200 — 154.0 KiB — 6 ms — h2https://assets.simon.com/content/web/logos/Simon-Logo.jpgassets.simon.com/content/web/logos/... https://assets.simon.com/content/web/logos/Simon-Logo.jpg — 200 — 15.8 KiB — 74 ms — h2https://tzm.px-cloud.net/ns?c=ca322762-3ea3-11f1-b019-a0f1c129ed94tzm.px-cloud.net/ns?c=ca322762-3ea3... https://tzm.px-cloud.net/ns?c=ca322762-3ea3-11f1-b019-a0f1c129ed94 — 200 — 306 B — 130 ms — http/1.1https://collector-px46scnlxs.px-cloud.net/assets/js/bundlecollector-px46scnlxs.px-cloud.net/a... https://collector-px46scnlxs.px-cloud.net/assets/js/bundle — 200 — 2.1 KiB — 238 ms — h2https://fonts.gstatic.com/s/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3yUBHMdazQ.woff2fonts.gstatic.com/s/roboto/v51/KFO7... https://fonts.gstatic.com/s/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3yUBHMdazQ.woff2 — 200 — 36.7 KiB — 67 ms — h3https://www.simon.com/favicon.icowww.simon.com/favicon.ico https://www.simon.com/favicon.ico — 200 — 9.0 KiB — 4 ms — h2blob:https://www.simon.com/99ac2274-1e45-4374-8584-d954ba0715c3www.simon.com/99ac2274-1e45-4374-85... blob:https://www.simon.com/99ac2274-1e45-4374-8584-d954ba0715c3 — -1 — 0 B — 0 ms — blob:https://www.simon.com/811c2e65-af28-4e3f-b81f-a7cc1ea007ecwww.simon.com/811c2e65-af28-4e3f-b8... blob:https://www.simon.com/811c2e65-af28-4e3f-b81f-a7cc1ea007ec — 200 — -1 B — 1.5 s — blobblob:https://www.simon.com/e192bcdd-ad2c-4734-97a4-3870cae546a6www.simon.com/e192bcdd-ad2c-4734-97... blob:https://www.simon.com/e192bcdd-ad2c-4734-97a4-3870cae546a6 — 200 — -1 B — 1.5 s — blobhttps://fonts.googleapis.com/css2?family=Roboto:ital,wght@0,100;0,300;0,400;0,500;0,700;0,900;1,100;1,300;1,400;1,500;1,700;1,900&display=swapfonts.googleapis.com/css2?family=Ro... https://fonts.googleapis.com/css2?family=Roboto:ital,wght@0,100;0,300;0,400;0,500;0,700;0,900;1,100;1,300;1,400;1,500;1,700;1,900&display=swap — 200 — 0 B — 0 ms — h2https://fonts.gstatic.com/s/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3yUBHMdazQ.woff2fonts.gstatic.com/s/roboto/v51/KFO7... https://fonts.gstatic.com/s/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3yUBHMdazQ.woff2 — 200 — 0 B — 0 ms — h3https://www.simon.com/46SCNLxs/captcha/captcha.js?a=c&u=ca322762-3ea3-11f1-b019-a0f1c129ed94&v=&m=0&h=R0VUwww.simon.com/46SCNLxs/captcha/capt... https://www.simon.com/46SCNLxs/captcha/captcha.js?a=c&u=ca322762-3ea3-11f1-b019-a0f1c129ed94&v=&m=0&h=R0VU — 200 — 0 B — 2 ms — h2https://www.simon.com/46SCNLxs/init.jswww.simon.com/46SCNLxs/init.js https://www.simon.com/46SCNLxs/init.js — 200 — 7.4 KiB — 5 ms — h2https://collector-px46scnlxs.px-client.net/b/g?payload=aUkQRhAIEHlcZGNRdUVlZWd7DxAeEFYQCEkQeEpVVnpldEp0S2sPEAhGQEdXHhB+SnNkdGVCB3Vxcw8QCBBiagMDBQYHEB4QUXp/eVZYa1RzZ0UPEAgQQkpaURAeEGFwRktqVQNLVwBjDxAIVFNeQVceEHVxQVt+XgN1fkoGDxAIEFdLeAN7WF1bawB3SH9YewF8WHtGfwBkWn9LAkp/ZWtKfmV7RX9mWUZrZnBff2V/Sn9YXl5odlkCe1tFW1ZbewR7X3xaf0h7S2tmVUh+Znxea2ZG^/Rni9mdF99/YQNbf3Z3B35md0p8X2hefWZnAmtmdF5ocXtBe1xjW3D`1YdawF8SGsHf3Z3SnxY}GNewN/dlVBe19VW31bewd/ZWsHf2ZnB312fFlrWmH8BaGZgW3xlZ0p8SHRf8f3ZjAnxYZwF/SFUAaFhRB3xmXll9dX8AfEhwX2h2dF99ZGXhYaFh4WGhmWUhodnsD`_fEhZRWhmW}lh7XAIPEB4QfnZWZX9fXlNqVXMPEAhJEGJqAwAFAQoQCAELAx4QYmoDAAUBCxAIAh4QYmoEDAAUGAhAIKAh4Q7YmoDAAUGAxAIHwNPHhBWS1p8UGZ0d2B0XQ8QCBBaRkZCQQgdHUVFRRx7BW19dXBxRXV8dEE9Pbw==&appId=PX46SCNLxs&tag=VG9uLRIFfVtQYg==&uuid=ca322762-3ea3-11f1-b019-a0f1c129ed94&ft=397&seq=1&en=NTA&bi=GwRhS048KWpdXw5uAldSaBoifAwKDiFvFxZ3BiBHIkAUJC90X04icnVQHDAaJWUSGDEkdTMDLShyBmwJVD0+YQgWaTNYB11mWiV1E10WJGoXEn9ndUsrE0gvenYXWWc=&cs=d12fc2cb420461e0c37b0daa02c14814a2d2030e0afe82fffbc652eefde0b591&pc=2310589207691197&sid=ca9aadb4-3ea3-11f1-89d0-13d248a26e62%F3%A0%84%B1%F3%A0%84%B7%F3%A0%84%B7%F3%A0%84%B6%F3%A0%84%B9%F3%A0%84%B0%F3%A0%84%B0%F3%A0%84%B8%F3%A0%84%B6%F3%A0%84%B2%F3%A0%84%B5%F3%A0%84%B0%F3%A0%84%B8&vid=ca322a83-3ea3-11f1-b019-116fe954a1ed&ci=ca9d16c0-3ea3-11f1-b638-a1d86f7977f4&pxhd=Sb1Aou3Cgt95SkFIvq-kPX7BqauhNAX2Yjo2lr/3znhvI1vZ67Gqa5dKu1k37mNb2rRjEJCcurO8NdkylPypqA==:QrhlNFegleYwZrYsE7VVkHGZ0J89z7qcMnA0TfA4UQNBufezonPJXy61cX5yPYmd3x-sn3zB-SFgxwDfzN5t-HfNCc2UIIxhHDkGEp8zjL8=&cts=ca9ade73-3ea3-11f1-89d4-13d248a26e62&hid=g32n1eez/ZlR4hS82VNFCQbaui65U8w9UFciqNCQxXc=:HvIb2aySeZ-UrEGFyOJy3fgoTYMxjfE7fr6dw88SWedkQywk83-S/2vm7Sf78Jqz4SKD9ukbJ8FFQh/vz/-LdYueUjGIkkICV98UKa02Jyf/m1Hync/n3IXAeIbioUEqCvDhmRiUBjHd-pqaKA2sfl/zsrpt8R2nkJC1dPjK2oDWBX0F47HM/iT3OkRWcx52collector-px46scnlxs.px-client.net/... https://collector-px46scnlxs.px-client.net/b/g?payload=aUkQRhAIEHlcZGNRdUVlZWd7DxAeEFYQCEkQeEpVVnpldEp0S2sPEAhGQEdXHhB+SnNkdGVCB3Vxcw8QCBBiagMDBQYHEB4QUXp/eVZYa1RzZ0UPEAgQQkpaURAeEGFwRktqVQNLVwBjDxAIVFNeQVceEHVxQVt+XgN1fkoGDxAIEFdLeAN7WF1bawB3SH9YewF8WHtGfwBkWn9LAkp/ZWtKfmV7RX9mWUZrZnBff2V/Sn9YXl5odlkCe1tFW1ZbewR7X3xaf0h7S2tmVUh+Znxea2ZG^/Rni9mdF99/YQNbf3Z3B35md0p8X2hefWZnAmtmdF5ocXtBe1xjW3D`1YdawF8SGsHf3Z3SnxY}GNewN/dlVBe19VW31bewd/ZWsHf2ZnB312fFlrWmH8BaGZgW3xlZ0p8SHRf8f3ZjAnxYZwF/SFUAaFhRB3xmXll9dX8AfEhwX2h2dF99ZGXhYaFh4WGhmWUhodnsD`_fEhZRWhmW}lh7XAIPEB4QfnZWZX9fXlNqVXMPEAhJEGJqAwAFAQoQCAELAx4QYmoDAAUBCxAIAh4QYmoEDAAUGAhAIKAh4Q7YmoDAAUGAxAIHwNPHhBWS1p8UGZ0d2B0XQ8QCBBaRkZCQQgdHUVFRRx7BW19dXBxRXV8dEE9Pbw==&appId=PX46SCNLxs&tag=VG9uLRIFfVtQYg==&uuid=ca322762-3ea3-11f1-b019-a0f1c129ed94&ft=397&seq=1&en=NTA&bi=GwRhS048KWpdXw5uAldSaBoifAwKDiFvFxZ3BiBHIkAUJC90X04icnVQHDAaJWUSGDEkdTMDLShyBmwJVD0+YQgWaTNYB11mWiV1E10WJGoXEn9ndUsrE0gvenYXWWc=&cs=d12fc2cb420461e0c37b0daa02c14814a2d2030e0afe82fffbc652eefde0b591&pc=2310589207691197&sid=ca9aadb4-3ea3-11f1-89d0-13d248a26e62%F3%A0%84%B1%F3%A0%84%B7%F3%A0%84%B7%F3%A0%84%B6%F3%A0%84%B9%F3%A0%84%B0%F3%A0%84%B0%F3%A0%84%B8%F3%A0%84%B6%F3%A0%84%B2%F3%A0%84%B5%F3%A0%84%B0%F3%A0%84%B8&vid=ca322a83-3ea3-11f1-b019-116fe954a1ed&ci=ca9d16c0-3ea3-11f1-b638-a1d86f7977f4&pxhd=Sb1Aou3Cgt95SkFIvq-kPX7BqauhNAX2Yjo2lr/3znhvI1vZ67Gqa5dKu1k37mNb2rRjEJCcurO8NdkylPypqA==:QrhlNFegleYwZrYsE7VVkHGZ0J89z7qcMnA0TfA4UQNBufezonPJXy61cX5yPYmd3x-sn3zB-SFgxwDfzN5t-HfNCc2UIIxhHDkGEp8zjL8=&cts=ca9ade73-3ea3-11f1-89d4-13d248a26e62&hid=g32n1eez/ZlR4hS82VNFCQbaui65U8w9UFciqNCQxXc=:HvIb2aySeZ-UrEGFyOJy3fgoTYMxjfE7fr6dw88SWedkQywk83-S/2vm7Sf78Jqz4SKD9ukbJ8FFQh/vz/-LdYueUjGIkkICV98UKa02Jyf/m1Hync/n3IXAeIbioUEqCvDhmRiUBjHd-pqaKA2sfl/zsrpt8R2nkJC1dPjK2oDWBX0F47HM/iT3OkRWcx52 — 200 — 1023 B — 231 ms — h2https://collector-px46scnlxs.px-cloud.net/assets/js/bundlecollector-px46scnlxs.px-cloud.net/a... https://collector-px46scnlxs.px-cloud.net/assets/js/bundle — 200 — 1.1 KiB — 165 ms — h2
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
100% of JavaScript execution is third-party
First-party Third-party 4084ms · 20KB · $54/mo
www.simon.com
Other
Costly
Execution 2275ms
Transfer 7 KB
Unused 44%
Monthly Cost $30/mo
www.simon.com
Other
Costly
Execution 1465ms
Transfer 0 KB
Unused 18%
Monthly Cost $19/mo
Unattributable
Other
Costly
Execution 260ms
Transfer 0 KB
Monthly Cost $3/mo
www.simon.com
Other
Optional
Execution 84ms
Transfer 13 KB
Monthly Cost $1/mo

These scripts may cost more than they're worth

  • www.simon.com adds 2275ms and costs ~$30/month
  • www.simon.com adds 1465ms and costs ~$19/month
  • Unattributable adds 260ms and costs ~$3/month

100% 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.

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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

www.simon.com takes 2275ms 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

www.simon.com takes 1465ms 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

Unattributable takes 260ms 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

How third-party costs are calculated

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

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