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Performance

· 15 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
87
GRADE
B
FIX
1
REVIEW
3
PASS
9
INFO
2

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

Mobile Desktop
80
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
77
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
96
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
85
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.

679 ms

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

989 ms

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

14 ms

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

0.403

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

679 ms

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

1.23 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
15
9 PASS 3 REVIEW 1 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 (695.1 KiB of 695.3 KiB)
Info::
Third-party blocking time is low (0 ms)
100%
First-party Third-party
C
Image Optimization
Action
15 images, 0 KB saveable
REVIEW
15 images, 0 KB saveable
Warning::
https://www.isc.org/images/blog/bind9label.jpg is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.isc.org/images/logo.png is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.isc.org/images/blog/net.jpg is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
15 images 193 KB
0 oversized -0 KB
9 legacy format
3 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

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

B
JS Bundles
7 scripts, 82 KB unused
REVIEW
7 scripts, 82 KB unused
Warning::
https://www.googletagmanager.com/gtag/js?id=G-EF66...: 56 KB unused (33%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.isc.org/js/bundle.js: 26 KB unused (79%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 82 KB
82 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.googletagmanager.com/gtag/js?id=G-EF669E5YC2173 KB56 KB (33%)✓3rd
https://www.isc.org/js/bundle.js33 KB26 KB (79%)✓3rd
https://www.isc.org/plugins/modernizr/modernizr-custom.js6 KB—✓3rd
https://ajax.googleapis.com/ajax/libs/jquery/3.7.1/jquery.min.js30 KB—✓3rd
https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.3/umd/popper.min.js7 KB—✓3rd
https://cdn.jsdelivr.net/npm/bootstrap@4.1.3/dist/js/bootstrap.min.js15 KB—✓3rd
https://googleads.g.doubleclick.net/pagead/viewthroughconversion/936311422/?random=1776800778962&cv=11&fst=1776800778962&bg=ffffff&guid=ON&async=1&en=gtag.config&gtm=45je64k0h2v879281285za200zd879281285xec&gcd=13l3l3l3l1l1&dma=0&tag_exp=0~115938465~115938469~117266401~117884344&u_w=800&u_h=600&url=https%3A%2F%2Fwww.isc.org%2F&rcb=4&frm=0&tiba=ISC%20-%20ISC&hn=www.googleadservices.com&npa=0&pscdl=noapi&auid=689187831.1776800779&uaa=x86&uab=64&uafvl=Not-A.Brand%3B24.0.0.0%7CChromium%3B146.0.7680.164&uamb=0&uam=&uap=macOS&uapv=10.15.7&uaw=0&data=event%3Dgtag.config&rfmt=3&fmt=42 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

C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A+
Page Weight Budget
695 KB transferred, 33 requests
PASS
695 KB transferred, 33 requests
Info::
Page weighs 1.3 MB (695 KB transferred)
Info::
33 HTTP requests
Info::
Estimated 0.14 g CO2 per page load
695 KB / 2.4 MB budget
695 KB transferred
33 requests
0.14 g CO2 per page load
JavaScript 265.6 KiB 38%
Images 192.7 KiB 28%
Other 139.2 KiB 20%
Fonts 55.2 KiB 8%
CSS 33.5 KiB 5%
HTML 8.5 KiB 1%
Other 587 B 0%
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+
JS Execution Cost
391ms total JS execution
PASS
391ms total JS execution
Info::
https://www.isc.org/: 170ms CPU time
Info::
https://www.googletagmanager.com/gtag/js?id=G-EF66...: 125ms CPU time
Info::
Unattributable: 95ms CPU time
Warning::
Third-party scripts: 391ms (100% of total)

Main Thread Breakdown

Other 32% Script Evaluation 32% Style & Layout 21% Script Parsing & Compilation 9% Rendering 4%
ScriptTotalScriptingParse/CompileParty
https://www.isc.org/170ms4ms1ms3rd
https://www.googletagmanager.com/gtag/js?id=G-EF669E5YC2125ms91ms33ms3rd
Unattributable95ms3ms0ms3rd
A+
Font Loading
1 fonts (55 KB)
PASS
1 fonts (55 KB)
Info::
1 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

1

55 KB total

Render-blocking

0

of 1

Dominant font-display

swap

Most common across fonts

Font loading timeline
Transfer FOIT (block) FOUT (swap)
0 ms 500 ms 1.0 s FCP 679 ms LCP 989 mshttps://cdn.jsdelivr.net/gh/lykmapipo/themify-icons@0.1.2/fonts/themify.woffthemify.woff https://cdn.jsdelivr.net/gh/lykmapipo/themify-icons@0.1.2/fonts/themify.woff — 55.2 KiB — 16 ms — font-display: swap
themify.woff woff swap
Size 55 KB
Load time 16 ms
Start 221 ms
Risk FOUT — text flashes from fallback to web font
  • Convert to woff2 for ~30% smaller file size
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 ~17 KB and ~34 ms

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
Page Weight Inventory
33 resources · 695 KB · 82 KB savings available
PASS
33 resources · 695 KB · 82 KB savings available
Info::
Within 1MB page-weight target
Got: 695 KB
Info::
~82 KB of savings available
Warning::
32 third-party resources (100% of weight)
33 resources · 695.3 KiB · 32 third-party Within 1MB page-weight target
Image 48% · 331.7 KiB
JavaScript 38% · 265.6 KiB
Font 8% · 55.2 KiB
CSS 5% · 33.5 KiB
Document 1% · 8.5 KiB
Other 0% · 783 B

~81.9 KiB of savings available

Remove unused JavaScript: 81.9 KiB
A
HTTP Caching
max-age=86400 (1 day)
PASS
max-age=86400 (1 day)
Info::
Cache-Control header is set
Got: max-age=86400
Info::
Effective TTL: 1 day (max-age=86400)
Info::
No ETag or Last-Modified header
Conditional requests (304 Not Modified) are not possible without validators.
Cache-Control

max-age=86400

DirectiveValueMeaning
max-age86400Cache for 1 day
Effective TTL: 86400 seconds
Network Waterfall
33 requests over 570ms
INFO
0 ms 500 ms 1.0 s FCP 679 ms LCP 989 mshttps://isc.org// https://isc.org/ — 301 — 216 B — 13 ms — h2https://www.isc.org/www.isc.org/ https://www.isc.org/ — 200 — 8.5 KiB — 19 ms — h2https://cdn.jsdelivr.net/gh/lykmapipo/themify-icons@0.1.2/css/themify-icons.csscdn.jsdelivr.net/gh/lykmapipo/themi... https://cdn.jsdelivr.net/gh/lykmapipo/themify-icons@0.1.2/css/themify-icons.css — 200 — 3.3 KiB — 56 ms — h2https://cdn.jsdelivr.net/npm/bootstrap@4.1.3/dist/css/bootstrap.min.csscdn.jsdelivr.net/npm/bootstrap@4.1.... https://cdn.jsdelivr.net/npm/bootstrap@4.1.3/dist/css/bootstrap.min.css — 200 — 23.2 KiB — 60 ms — h2https://www.isc.org/scss/style.min.csswww.isc.org/scss/style.min.css https://www.isc.org/scss/style.min.css — 200 — 7.0 KiB — 20 ms — h2https://www.isc.org/plugins/modernizr/modernizr-custom.jswww.isc.org/plugins/modernizr/moder... https://www.isc.org/plugins/modernizr/modernizr-custom.js — 200 — 5.8 KiB — 8 ms — h2https://www.isc.org/images/logo.pngwww.isc.org/images/logo.png https://www.isc.org/images/logo.png — 200 — 10.8 KiB — 17 ms — h2https://www.isc.org/images/bind9.pngwww.isc.org/images/bind9.png https://www.isc.org/images/bind9.png — 200 — 15.7 KiB — 14 ms — h2https://www.isc.org/images/kea.pngwww.isc.org/images/kea.png https://www.isc.org/images/kea.png — 200 — 18.1 KiB — 7 ms — h2https://www.isc.org/images/stork80x.pngwww.isc.org/images/stork80x.png https://www.isc.org/images/stork80x.png — 200 — 6.4 KiB — 10 ms — h2data:image/webp;base64,UklGRiQAAABXRUJQVlA4IBgAAAAwAQCdASoBAAEAAwA0JaQAA3AA/vuUAAA=data:image/webp;base64,UklGRiQAAABX... data:image/webp;base64,UklGRiQAAABXRUJQVlA4IBgAAAAwAQCdASoBAAEAAwA0JaQAA3AA/vuUAAA= — 200 — 0 B — 0 ms — datahttps://www.isc.org/images/dhcp.pngwww.isc.org/images/dhcp.png https://www.isc.org/images/dhcp.png — 200 — 10.2 KiB — 9 ms — h2data:image/webp;base64,UklGRkoAAABXRUJQVlA4WAoAAAAQAAAAAAAAAAAAQUxQSAwAAAABBxAR/Q9ERP8DAABWUDggGAAA…data:image/webp;base64,UklGRkoAAABX... data:image/webp;base64,UklGRkoAAABXRUJQVlA4WAoAAAAQAAAAAAAAAAAAQUxQSAwAAAABBxAR/Q9ERP8DAABWUDggGAAA… — 200 — 0 B — 0 ms — datadata:image/webp;base64,UklGRlIAAABXRUJQVlA4WAoAAAASAAAAAAAAAAAAQU5JTQYAAAD/////AABBTk1GJgAAAAAAAAAA…data:image/webp;base64,UklGRlIAAABX... data:image/webp;base64,UklGRlIAAABXRUJQVlA4WAoAAAASAAAAAAAAAAAAQU5JTQYAAAD/////AABBTk1GJgAAAAAAAAAA… — 200 — 0 B — 0 ms — datadata:image/webp;base64,UklGRh4AAABXRUJQVlA4TBEAAAAvAAAAAAfQ//73v/+BiOh/AAA=data:image/webp;base64,UklGRh4AAABX... data:image/webp;base64,UklGRh4AAABXRUJQVlA4TBEAAAAvAAAAAAfQ//73v/+BiOh/AAA= — 200 — 0 B — 0 ms — datahttps://ajax.googleapis.com/ajax/libs/jquery/3.7.1/jquery.min.jsajax.googleapis.com/ajax/libs/jquer... https://ajax.googleapis.com/ajax/libs/jquery/3.7.1/jquery.min.js — 200 — 30.4 KiB — 71 ms — h2https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.3/umd/popper.min.jscdnjs.cloudflare.com/ajax/libs/popp... https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.3/umd/popper.min.js — 200 — 6.9 KiB — 51 ms — h3https://cdn.jsdelivr.net/npm/bootstrap@4.1.3/dist/js/bootstrap.min.jscdn.jsdelivr.net/npm/bootstrap@4.1.... https://cdn.jsdelivr.net/npm/bootstrap@4.1.3/dist/js/bootstrap.min.js — 200 — 14.9 KiB — 55 ms — h2https://www.googletagmanager.com/gtag/js?id=G-EF669E5YC2www.googletagmanager.com/gtag/js?id... https://www.googletagmanager.com/gtag/js?id=G-EF669E5YC2 — 200 — 172.5 KiB — 200 ms — h2https://www.isc.org/images/blog/bind9label.jpgwww.isc.org/images/blog/bind9label.... https://www.isc.org/images/blog/bind9label.jpg — 200 — 5.4 KiB — 30 ms — h2https://www.isc.org/images/blog/net.jpgwww.isc.org/images/blog/net.jpg https://www.isc.org/images/blog/net.jpg — 200 — 33.3 KiB — 29 ms — h2https://www.isc.org/js/bundle.jswww.isc.org/js/bundle.js https://www.isc.org/js/bundle.js — 200 — 33.0 KiB — 39 ms — h2https://cdn.jsdelivr.net/gh/lykmapipo/themify-icons@0.1.2/css/themify-icons.csscdn.jsdelivr.net/gh/lykmapipo/themi... https://cdn.jsdelivr.net/gh/lykmapipo/themify-icons@0.1.2/css/themify-icons.css — 200 — 0 B — 24 ms — h2https://www.isc.org/images/backgrounds/banner.webpwww.isc.org/images/backgrounds/bann... https://www.isc.org/images/backgrounds/banner.webp — 200 — 69.7 KiB — 32 ms — h2https://www.isc.org/images/banner/banner-dots.pngwww.isc.org/images/banner/banner-do... https://www.isc.org/images/banner/banner-dots.png — 200 — 19.4 KiB — 25 ms — h2https://www.isc.org/images/backgrounds/footer.webpwww.isc.org/images/backgrounds/foot... https://www.isc.org/images/backgrounds/footer.webp — 200 — 3.7 KiB — 27 ms — h2https://cdn.jsdelivr.net/gh/lykmapipo/themify-icons@0.1.2/fonts/themify.woffcdn.jsdelivr.net/gh/lykmapipo/themi... https://cdn.jsdelivr.net/gh/lykmapipo/themify-icons@0.1.2/fonts/themify.woff — 200 — 55.2 KiB — 16 ms — h2https://www.google-analytics.com/g/collect?v=2&tid=G-EF669E5YC2&gtm=45je64k0h2v879281285za200zd879281285&_p=1776800778619&gcd=13l3l3l3l1l1&npa=0&dma=0&_geo=1&_rdi=1&are=1&cid=764575798.1776800779&frm=0&pscdl=noapi&rcb=4&ul=en-us&_s=1&tag_exp=0~115938465~115938469~117266401~117884344&sid=1776800778&sct=1&seg=0&dl=https%3A%2F%2Fwww.isc.org%2F&dt=ISC%20-%20ISC&en=page_view&_fv=1&_nsi=1&_ss=1&_ee=1&tfd=435www.google-analytics.com/g/collect?... https://www.google-analytics.com/g/collect?v=2&tid=G-EF669E5YC2&gtm=45je64k0h2v879281285za200zd879281285&_p=1776800778619&gcd=13l3l3l3l1l1&npa=0&dma=0&_geo=1&_rdi=1&are=1&cid=764575798.1776800779&frm=0&pscdl=noapi&rcb=4&ul=en-us&_s=1&tag_exp=0~115938465~115938469~117266401~117884344&sid=1776800778&sct=1&seg=0&dl=https%3A%2F%2Fwww.isc.org%2F&dt=ISC%20-%20ISC&en=page_view&_fv=1&_nsi=1&_ss=1&_ee=1&tfd=435 — 204 — 546 B — 56 ms — h2https://googleads.g.doubleclick.net/pagead/viewthroughconversion/936311422/?random=1776800778962&cv=11&fst=1776800778962&bg=ffffff&guid=ON&async=1&en=gtag.config&gtm=45je64k0h2v879281285za200zd879281285xec&gcd=13l3l3l3l1l1&dma=0&tag_exp=0~115938465~115938469~117266401~117884344&u_w=800&u_h=600&url=https%3A%2F%2Fwww.isc.org%2F&rcb=4&frm=0&tiba=ISC%20-%20ISC&hn=www.googleadservices.com&npa=0&pscdl=noapi&auid=689187831.1776800779&uaa=x86&uab=64&uafvl=Not-A.Brand%3B24.0.0.0%7CChromium%3B146.0.7680.164&uamb=0&uam=&uap=macOS&uapv=10.15.7&uaw=0&data=event%3Dgtag.config&rfmt=3&fmt=4googleads.g.doubleclick.net/pagead/... https://googleads.g.doubleclick.net/pagead/viewthroughconversion/936311422/?random=1776800778962&cv=11&fst=1776800778962&bg=ffffff&guid=ON&async=1&en=gtag.config&gtm=45je64k0h2v879281285za200zd879281285xec&gcd=13l3l3l3l1l1&dma=0&tag_exp=0~115938465~115938469~117266401~117884344&u_w=800&u_h=600&url=https%3A%2F%2Fwww.isc.org%2F&rcb=4&frm=0&tiba=ISC%20-%20ISC&hn=www.googleadservices.com&npa=0&pscdl=noapi&auid=689187831.1776800779&uaa=x86&uab=64&uafvl=Not-A.Brand%3B24.0.0.0%7CChromium%3B146.0.7680.164&uamb=0&uam=&uap=macOS&uapv=10.15.7&uaw=0&data=event%3Dgtag.config&rfmt=3&fmt=4 — 200 — 2.1 KiB — 61 ms — h3https://www.google.com/rmkt/collect/936311422/?random=1776800778962&cv=11&fst=1776800778962&fmt=8&bg=ffffff&guid=ON&async=1&en=gtag.config&gtm=45je64k0h2v879281285za200zd879281285xec&gcd=13l3l3l3l1l1&dma=0&tag_exp=0~115938465~115938469~117266401~117884344&u_w=800&u_h=600&url=https%3A%2F%2Fwww.isc.org%2F&rcb=4&frm=0&tiba=ISC%20-%20ISC&hn=www.googleadservices.com&npa=0&pscdl=noapi&auid=689187831.1776800779&uaa=x86&uab=64&uafvl=Not-A.Brand%3B24.0.0.0%7CChromium%3B146.0.7680.164&uamb=0&uam=&uap=macOS&uapv=10.15.7&uaw=0&data=event%3Dgtag.config&gcp=5www.google.com/rmkt/collect/9363114... https://www.google.com/rmkt/collect/936311422/?random=1776800778962&cv=11&fst=1776800778962&fmt=8&bg=ffffff&guid=ON&async=1&en=gtag.config&gtm=45je64k0h2v879281285za200zd879281285xec&gcd=13l3l3l3l1l1&dma=0&tag_exp=0~115938465~115938469~117266401~117884344&u_w=800&u_h=600&url=https%3A%2F%2Fwww.isc.org%2F&rcb=4&frm=0&tiba=ISC%20-%20ISC&hn=www.googleadservices.com&npa=0&pscdl=noapi&auid=689187831.1776800779&uaa=x86&uab=64&uafvl=Not-A.Brand%3B24.0.0.0%7CChromium%3B146.0.7680.164&uamb=0&uam=&uap=macOS&uapv=10.15.7&uaw=0&data=event%3Dgtag.config&gcp=5 — 200 — 20 B — 55 ms — h3
0 ms 500 ms 1.0 s FCP 679 ms LCP 989 mshttps://isc.org// https://isc.org/ — 301 — 216 B — 13 ms — h2https://www.isc.org/www.isc.org/ https://www.isc.org/ — 200 — 8.5 KiB — 19 ms — h2https://cdn.jsdelivr.net/gh/lykmapipo/themify-icons@0.1.2/css/themify-icons.csscdn.jsdelivr.net/gh/lykmapipo/themi... https://cdn.jsdelivr.net/gh/lykmapipo/themify-icons@0.1.2/css/themify-icons.css — 200 — 3.3 KiB — 56 ms — h2https://cdn.jsdelivr.net/npm/bootstrap@4.1.3/dist/css/bootstrap.min.csscdn.jsdelivr.net/npm/bootstrap@4.1.... https://cdn.jsdelivr.net/npm/bootstrap@4.1.3/dist/css/bootstrap.min.css — 200 — 23.2 KiB — 60 ms — h2https://www.isc.org/scss/style.min.csswww.isc.org/scss/style.min.css https://www.isc.org/scss/style.min.css — 200 — 7.0 KiB — 20 ms — h2https://www.isc.org/plugins/modernizr/modernizr-custom.jswww.isc.org/plugins/modernizr/moder... https://www.isc.org/plugins/modernizr/modernizr-custom.js — 200 — 5.8 KiB — 8 ms — h2https://www.isc.org/images/logo.pngwww.isc.org/images/logo.png https://www.isc.org/images/logo.png — 200 — 10.8 KiB — 17 ms — h2https://www.isc.org/images/bind9.pngwww.isc.org/images/bind9.png https://www.isc.org/images/bind9.png — 200 — 15.7 KiB — 14 ms — h2https://www.isc.org/images/kea.pngwww.isc.org/images/kea.png https://www.isc.org/images/kea.png — 200 — 18.1 KiB — 7 ms — h2https://www.isc.org/images/stork80x.pngwww.isc.org/images/stork80x.png https://www.isc.org/images/stork80x.png — 200 — 6.4 KiB — 10 ms — h2data:image/webp;base64,UklGRiQAAABXRUJQVlA4IBgAAAAwAQCdASoBAAEAAwA0JaQAA3AA/vuUAAA=data:image/webp;base64,UklGRiQAAABX... data:image/webp;base64,UklGRiQAAABXRUJQVlA4IBgAAAAwAQCdASoBAAEAAwA0JaQAA3AA/vuUAAA= — 200 — 0 B — 0 ms — datahttps://www.isc.org/images/dhcp.pngwww.isc.org/images/dhcp.png https://www.isc.org/images/dhcp.png — 200 — 10.2 KiB — 9 ms — h2data:image/webp;base64,UklGRkoAAABXRUJQVlA4WAoAAAAQAAAAAAAAAAAAQUxQSAwAAAABBxAR/Q9ERP8DAABWUDggGAAA…data:image/webp;base64,UklGRkoAAABX... data:image/webp;base64,UklGRkoAAABXRUJQVlA4WAoAAAAQAAAAAAAAAAAAQUxQSAwAAAABBxAR/Q9ERP8DAABWUDggGAAA… — 200 — 0 B — 0 ms — datadata:image/webp;base64,UklGRlIAAABXRUJQVlA4WAoAAAASAAAAAAAAAAAAQU5JTQYAAAD/////AABBTk1GJgAAAAAAAAAA…data:image/webp;base64,UklGRlIAAABX... data:image/webp;base64,UklGRlIAAABXRUJQVlA4WAoAAAASAAAAAAAAAAAAQU5JTQYAAAD/////AABBTk1GJgAAAAAAAAAA… — 200 — 0 B — 0 ms — datadata:image/webp;base64,UklGRh4AAABXRUJQVlA4TBEAAAAvAAAAAAfQ//73v/+BiOh/AAA=data:image/webp;base64,UklGRh4AAABX... data:image/webp;base64,UklGRh4AAABXRUJQVlA4TBEAAAAvAAAAAAfQ//73v/+BiOh/AAA= — 200 — 0 B — 0 ms — datahttps://ajax.googleapis.com/ajax/libs/jquery/3.7.1/jquery.min.jsajax.googleapis.com/ajax/libs/jquer... https://ajax.googleapis.com/ajax/libs/jquery/3.7.1/jquery.min.js — 200 — 30.4 KiB — 71 ms — h2https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.3/umd/popper.min.jscdnjs.cloudflare.com/ajax/libs/popp... https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.3/umd/popper.min.js — 200 — 6.9 KiB — 51 ms — h3https://cdn.jsdelivr.net/npm/bootstrap@4.1.3/dist/js/bootstrap.min.jscdn.jsdelivr.net/npm/bootstrap@4.1.... https://cdn.jsdelivr.net/npm/bootstrap@4.1.3/dist/js/bootstrap.min.js — 200 — 14.9 KiB — 55 ms — h2https://www.googletagmanager.com/gtag/js?id=G-EF669E5YC2www.googletagmanager.com/gtag/js?id... https://www.googletagmanager.com/gtag/js?id=G-EF669E5YC2 — 200 — 172.5 KiB — 200 ms — h2https://www.isc.org/images/blog/bind9label.jpgwww.isc.org/images/blog/bind9label.... https://www.isc.org/images/blog/bind9label.jpg — 200 — 5.4 KiB — 30 ms — h2https://www.isc.org/images/blog/net.jpgwww.isc.org/images/blog/net.jpg https://www.isc.org/images/blog/net.jpg — 200 — 33.3 KiB — 29 ms — h2https://www.isc.org/js/bundle.jswww.isc.org/js/bundle.js https://www.isc.org/js/bundle.js — 200 — 33.0 KiB — 39 ms — h2https://cdn.jsdelivr.net/gh/lykmapipo/themify-icons@0.1.2/css/themify-icons.csscdn.jsdelivr.net/gh/lykmapipo/themi... https://cdn.jsdelivr.net/gh/lykmapipo/themify-icons@0.1.2/css/themify-icons.css — 200 — 0 B — 24 ms — h2https://www.isc.org/images/backgrounds/banner.webpwww.isc.org/images/backgrounds/bann... https://www.isc.org/images/backgrounds/banner.webp — 200 — 69.7 KiB — 32 ms — h2https://www.isc.org/images/banner/banner-dots.pngwww.isc.org/images/banner/banner-do... https://www.isc.org/images/banner/banner-dots.png — 200 — 19.4 KiB — 25 ms — h2https://www.isc.org/images/backgrounds/footer.webpwww.isc.org/images/backgrounds/foot... https://www.isc.org/images/backgrounds/footer.webp — 200 — 3.7 KiB — 27 ms — h2https://cdn.jsdelivr.net/gh/lykmapipo/themify-icons@0.1.2/fonts/themify.woffcdn.jsdelivr.net/gh/lykmapipo/themi... https://cdn.jsdelivr.net/gh/lykmapipo/themify-icons@0.1.2/fonts/themify.woff — 200 — 55.2 KiB — 16 ms — h2https://www.google-analytics.com/g/collect?v=2&tid=G-EF669E5YC2&gtm=45je64k0h2v879281285za200zd879281285&_p=1776800778619&gcd=13l3l3l3l1l1&npa=0&dma=0&_geo=1&_rdi=1&are=1&cid=764575798.1776800779&frm=0&pscdl=noapi&rcb=4&ul=en-us&_s=1&tag_exp=0~115938465~115938469~117266401~117884344&sid=1776800778&sct=1&seg=0&dl=https%3A%2F%2Fwww.isc.org%2F&dt=ISC%20-%20ISC&en=page_view&_fv=1&_nsi=1&_ss=1&_ee=1&tfd=435www.google-analytics.com/g/collect?... https://www.google-analytics.com/g/collect?v=2&tid=G-EF669E5YC2&gtm=45je64k0h2v879281285za200zd879281285&_p=1776800778619&gcd=13l3l3l3l1l1&npa=0&dma=0&_geo=1&_rdi=1&are=1&cid=764575798.1776800779&frm=0&pscdl=noapi&rcb=4&ul=en-us&_s=1&tag_exp=0~115938465~115938469~117266401~117884344&sid=1776800778&sct=1&seg=0&dl=https%3A%2F%2Fwww.isc.org%2F&dt=ISC%20-%20ISC&en=page_view&_fv=1&_nsi=1&_ss=1&_ee=1&tfd=435 — 204 — 546 B — 56 ms — h2https://googleads.g.doubleclick.net/pagead/viewthroughconversion/936311422/?random=1776800778962&cv=11&fst=1776800778962&bg=ffffff&guid=ON&async=1&en=gtag.config&gtm=45je64k0h2v879281285za200zd879281285xec&gcd=13l3l3l3l1l1&dma=0&tag_exp=0~115938465~115938469~117266401~117884344&u_w=800&u_h=600&url=https%3A%2F%2Fwww.isc.org%2F&rcb=4&frm=0&tiba=ISC%20-%20ISC&hn=www.googleadservices.com&npa=0&pscdl=noapi&auid=689187831.1776800779&uaa=x86&uab=64&uafvl=Not-A.Brand%3B24.0.0.0%7CChromium%3B146.0.7680.164&uamb=0&uam=&uap=macOS&uapv=10.15.7&uaw=0&data=event%3Dgtag.config&rfmt=3&fmt=4googleads.g.doubleclick.net/pagead/... https://googleads.g.doubleclick.net/pagead/viewthroughconversion/936311422/?random=1776800778962&cv=11&fst=1776800778962&bg=ffffff&guid=ON&async=1&en=gtag.config&gtm=45je64k0h2v879281285za200zd879281285xec&gcd=13l3l3l3l1l1&dma=0&tag_exp=0~115938465~115938469~117266401~117884344&u_w=800&u_h=600&url=https%3A%2F%2Fwww.isc.org%2F&rcb=4&frm=0&tiba=ISC%20-%20ISC&hn=www.googleadservices.com&npa=0&pscdl=noapi&auid=689187831.1776800779&uaa=x86&uab=64&uafvl=Not-A.Brand%3B24.0.0.0%7CChromium%3B146.0.7680.164&uamb=0&uam=&uap=macOS&uapv=10.15.7&uaw=0&data=event%3Dgtag.config&rfmt=3&fmt=4 — 200 — 2.1 KiB — 61 ms — h3https://www.google.com/rmkt/collect/936311422/?random=1776800778962&cv=11&fst=1776800778962&fmt=8&bg=ffffff&guid=ON&async=1&en=gtag.config&gtm=45je64k0h2v879281285za200zd879281285xec&gcd=13l3l3l3l1l1&dma=0&tag_exp=0~115938465~115938469~117266401~117884344&u_w=800&u_h=600&url=https%3A%2F%2Fwww.isc.org%2F&rcb=4&frm=0&tiba=ISC%20-%20ISC&hn=www.googleadservices.com&npa=0&pscdl=noapi&auid=689187831.1776800779&uaa=x86&uab=64&uafvl=Not-A.Brand%3B24.0.0.0%7CChromium%3B146.0.7680.164&uamb=0&uam=&uap=macOS&uapv=10.15.7&uaw=0&data=event%3Dgtag.config&gcp=5www.google.com/rmkt/collect/9363114... https://www.google.com/rmkt/collect/936311422/?random=1776800778962&cv=11&fst=1776800778962&fmt=8&bg=ffffff&guid=ON&async=1&en=gtag.config&gtm=45je64k0h2v879281285za200zd879281285xec&gcd=13l3l3l3l1l1&dma=0&tag_exp=0~115938465~115938469~117266401~117884344&u_w=800&u_h=600&url=https%3A%2F%2Fwww.isc.org%2F&rcb=4&frm=0&tiba=ISC%20-%20ISC&hn=www.googleadservices.com&npa=0&pscdl=noapi&auid=689187831.1776800779&uaa=x86&uab=64&uafvl=Not-A.Brand%3B24.0.0.0%7CChromium%3B146.0.7680.164&uamb=0&uam=&uap=macOS&uapv=10.15.7&uaw=0&data=event%3Dgtag.config&gcp=5 — 200 — 20 B — 55 ms — h3https://www.google.com/ccm/collect?rcb=4&frm=0&en=page_view&dl=https%3A%2F%2Fwww.isc.org%2F&scrsrc=www.googletagmanager.com&rnd=1702880588.1776800779&dt=ISC%20-%20ISC&auid=689187831.1776800779&navt=n&npa=0&gtm=45je64k0h2v879281285za200zd879281285xec&gcd=13l3l3l3l1l1&dma=0&tag_exp=0~115938465~115938469~117266401~117884344&apve=1&apvf=f&apvc=1&tids=AW-936311422&tid=AW-936311422&tft=1776800778983&tfd=460www.google.com/ccm/collect?rcb=4&fr... https://www.google.com/ccm/collect?rcb=4&frm=0&en=page_view&dl=https%3A%2F%2Fwww.isc.org%2F&scrsrc=www.googletagmanager.com&rnd=1702880588.1776800779&dt=ISC%20-%20ISC&auid=689187831.1776800779&navt=n&npa=0&gtm=45je64k0h2v879281285za200zd879281285xec&gcd=13l3l3l3l1l1&dma=0&tag_exp=0~115938465~115938469~117266401~117884344&apve=1&apvf=f&apvc=1&tids=AW-936311422&tid=AW-936311422&tft=1776800778983&tfd=460 — 200 — 21 B — 54 ms — h3https://www.google.com/pagead/1p-user-list/936311422/?random=1776800778962&cv=11&fst=1776798000000&bg=ffffff&guid=ON&async=1&en=gtag.config&gtm=45je64k0h2v879281285za200zd879281285xec&gcd=13l3l3l3l1l1&dma=0&tag_exp=0~115938465~115938469~117266401~117884344&u_w=800&u_h=600&url=https%3A%2F%2Fwww.isc.org%2F&rcb=4&frm=0&tiba=ISC%20-%20ISC&hn=www.googleadservices.com&npa=0&pscdl=noapi&auid=689187831.1776800779&uaa=x86&uab=64&uafvl=Not-A.Brand%3B24.0.0.0%7CChromium%3B146.0.7680.164&uamb=0&uam=&uap=macOS&uapv=10.15.7&uaw=0&data=event%3Dgtag.config&rfmt=3&fmt=3&is_vtc=1&cid=CAQSsAEABaugfeJIqQ2d3zVy_EH_4ItsV5KMe2X8A5Izx332eA62gn1oqh4am02aX_ekr6iX3UI3KYPY9ndPZvjPWn26HA0B2vy1-Q66Di1rKGKolG6le3DVJBDNeDLFocuQh4oM79tJlH1V7r2er_hkq5sakYhJY8wzYHiO0tp_qW5isYVLBO8DVySj6g3_MOd9ygfVVrpE7c3E8RJnCa2Sm0iLoEuJ8F9qVzaDH_w1p_OUlw&random=1629044189&rmt_tld=0&ipr=ywww.google.com/pagead/1p-user-list/... https://www.google.com/pagead/1p-user-list/936311422/?random=1776800778962&cv=11&fst=1776798000000&bg=ffffff&guid=ON&async=1&en=gtag.config&gtm=45je64k0h2v879281285za200zd879281285xec&gcd=13l3l3l3l1l1&dma=0&tag_exp=0~115938465~115938469~117266401~117884344&u_w=800&u_h=600&url=https%3A%2F%2Fwww.isc.org%2F&rcb=4&frm=0&tiba=ISC%20-%20ISC&hn=www.googleadservices.com&npa=0&pscdl=noapi&auid=689187831.1776800779&uaa=x86&uab=64&uafvl=Not-A.Brand%3B24.0.0.0%7CChromium%3B146.0.7680.164&uamb=0&uam=&uap=macOS&uapv=10.15.7&uaw=0&data=event%3Dgtag.config&rfmt=3&fmt=3&is_vtc=1&cid=CAQSsAEABaugfeJIqQ2d3zVy_EH_4ItsV5KMe2X8A5Izx332eA62gn1oqh4am02aX_ekr6iX3UI3KYPY9ndPZvjPWn26HA0B2vy1-Q66Di1rKGKolG6le3DVJBDNeDLFocuQh4oM79tJlH1V7r2er_hkq5sakYhJY8wzYHiO0tp_qW5isYVLBO8DVySj6g3_MOd9ygfVVrpE7c3E8RJnCa2Sm0iLoEuJ8F9qVzaDH_w1p_OUlw&random=1629044189&rmt_tld=0&ipr=y — 200 — 64 B — 31 ms — h3https://www.isc.org/images/favicon.icowww.isc.org/images/favicon.ico https://www.isc.org/images/favicon.ico — 200 — 139.0 KiB — 9 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 391ms · 181KB · $1/mo
www.isc.org
Other
Optional
Execution 170ms
Transfer 8 KB
Monthly Cost $1/mo
Google Tag Manager
Tag Manager
Optional
Execution 125ms
Transfer 173 KB
Unused 33%
Monthly Cost $0/mo
Unattributable
Other
Optional
Execution 95ms
Transfer 0 KB
Monthly Cost $0/mo

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.

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

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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