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Performance

· 17 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
90
GRADE
A
FIX
0
REVIEW
4
PASS
11
INFO
2

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

Mobile Desktop
82
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
79
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.
83
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.

1.75 s

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

4.69 s

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

0 ms

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

0.030

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

1.75 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.

4.69 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
11 PASS 4 REVIEW
C
Page Weight Budget
Action
1.6 MB transferred, 29 requests
REVIEW
1.6 MB transferred, 29 requests
Info::
Page weighs 1.9 MB (1.6 MB transferred)
Warning::
Images are 1.3 MB — compress or use modern formats
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
Got: 1.3 MB
Info::
29 HTTP requests
Info::
Estimated 0.34 g CO2 per page load
1.6 MB / 2.4 MB budget
1.6 MB transferred
29 requests
0.34 g CO2 per page load
Images 1.3 MiB 83%
Fonts 176.6 KiB 11%
JavaScript 45.4 KiB 3%
CSS 36.9 KiB 2%
HTML 24.1 KiB 1%
Other 336 B 0%
0 2.4 MB 4.9 MB
Approaching limit

Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.

Why this matters

Image bandwidth is high — modern formats (WebP/AVIF) and resizing typically cut it 50%+.

Source: web.dev

C
Image Optimization
Action
7 images, 0 KB saveable
REVIEW
7 images, 0 KB saveable
Warning::
https://krebsonsecurity.com/b-keeper/18.png is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://krebsonsecurity.com/b-doppel/16.png is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
7 images 1.3 MB
0 oversized -0 KB
7 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

B
JS Execution Cost
738ms total JS execution
REVIEW
738ms total JS execution
Warning::
https://krebsonsecurity.com/: 465ms CPU time
Info::
Unattributable: 173ms CPU time
Info::
https://krebsonsecurity.com/wp-includes/js/jquery/...: 99ms CPU time
Info::
Third-party scripts: 173ms (23% of total)

Main Thread Breakdown

Style & Layout 40% Other 28% Script Evaluation 21% Rendering 5% Parse HTML & CSS 4%
ScriptTotalScriptingParse/CompileParty
https://krebsonsecurity.com/465ms77ms2ms1st
Unattributable173ms5ms0ms3rd
https://krebsonsecurity.com/wp-includes/js/jquery/jquery.min.js?ver=3.6.499ms73ms8ms1st
C
Page Weight Inventory
Action
29 resources · 1.6 MB · 0 KB savings available
REVIEW
29 resources · 1.6 MB · 0 KB savings available
Warning::
Page weight 617 KB over 1MB target
Got: 1.6 MB Expected: ≤ 1 MB
Info::
5 third-party resources (7% of weight)
Info::
2 resources over 200KB
29 resources · 1.6 MiB · 5 third-party 617.0 KiB over 1MB target
Image 83% · 1.3 MiB
Font 11% · 176.6 KiB
JavaScript 3% · 45.4 KiB
CSS 2% · 36.9 KiB
Document 1% · 24.1 KiB
A+
Third-Party Impact
7% third-party, 0 ms blocking
PASS
7% third-party, 0 ms blocking
Info::
Third-party code accounts for 7% of page weight (108.5 KiB of 1.6 MiB)
Info::
Third-party blocking time is low (0 ms)
93%
First-party Third-party
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+
Font Loading
5 fonts (177 KB)
PASS
5 fonts (177 KB)
Info::
5 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

5

177 KB total

Render-blocking

0

of 5

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 1.8 s LCP 4.7 shttps://fonts.gstatic.com/s/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3yUBHMdazQ.woff2KFO7CnqEu92Fr1ME7kSn66a... https://fonts.gstatic.com/s/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3yUBHMdazQ.woff2 — 36.7 KiB — 52 ms — font-display: swaphttps://fonts.gstatic.com/s/roboto/v51/KFOKCnqEu92Fr1Mu53ZEC9_Vu3r1gIhOszmOClHrs6ljXfMMLoHQuAj-k3Yk128.woff2KFOKCnqEu92Fr1Mu53ZEC9_... https://fonts.gstatic.com/s/roboto/v51/KFOKCnqEu92Fr1Mu53ZEC9_Vu3r1gIhOszmOClHrs6ljXfMMLoHQuAj-k3Yk128.woff2 — 17.8 KiB — 51 ms — font-display: swaphttps://krebsonsecurity.com/wp-content/themes/kos-mar2021/fonts/fontawesome-webfont.woff2?v=4.6.3fontawesome-webfont.woff2 https://krebsonsecurity.com/wp-content/themes/kos-mar2021/fonts/fontawesome-webfont.woff2?v=4.6.3 — 70.2 KiB — 34 ms — font-display: swaphttps://fonts.gstatic.com/s/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMaxKUBHMdazTgWw.woff2KFO7CnqEu92Fr1ME7kSn66a... https://fonts.gstatic.com/s/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMaxKUBHMdazTgWw.woff2 — 16.3 KiB — 47 ms — font-display: swaphttps://fonts.gstatic.com/s/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMawCUBHMdazTgWw.woff2KFO7CnqEu92Fr1ME7kSn66a... https://fonts.gstatic.com/s/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMawCUBHMdazTgWw.woff2 — 35.5 KiB — 26 ms — font-display: swap
KFO7CnqEu92Fr1ME7kSn66a... woff2 swap
Size 37 KB
Load time 52 ms
Start 214 ms
Risk FOUT — text flashes from fallback to web font
KFOKCnqEu92Fr1Mu53ZEC9_... woff2 swap
Size 18 KB
Load time 51 ms
Start 214 ms
Risk FOUT — text flashes from fallback to web font
fontawesome-webfont.woff2 unknown swap
Size 70 KB
Load time 34 ms
Start 214 ms
Risk FOUT — text flashes from fallback to web font
KFO7CnqEu92Fr1ME7kSn66a... woff2 swap
Size 16 KB
Load time 47 ms
Start 217 ms
Risk FOUT — text flashes from fallback to web font
KFO7CnqEu92Fr1ME7kSn66a... woff2 swap
Size 35 KB
Load time 26 ms
Start 292 ms
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)

Fixing the unchecked items could save ~21 KB and ~42 ms

A+
JS Bundles
5 scripts, 0 KB unused
PASS
5 scripts, 0 KB unused
0 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://krebsonsecurity.com/wp-includes/js/jquery/jquery.min.js?ver=3.6.430 KB—✓1st
https://krebsonsecurity.com/wp-includes/js/jquery/jquery-migrate.min.js?ver=3.4.05 KB—✓1st
https://krebsonsecurity.com/wp-content/plugins/jquery-lightbox-for-native-galleries/colorbox/jquery.colorbox-min.js?ver=1.3.144 KB—✓1st
https://krebsonsecurity.com/wp-content/plugins/jspullquotes/resources/jspullquotes.js2 KB—✓1st
https://krebsonsecurity.com/wp-content/themes/kos-mar2021/js/slicknav.js?ver=6.2.24 KB—✓1st
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
1 hints, 0 missing preconnects
PASS
1 hints, 0 missing preconnects
Info::
Page uses 1 resource hint(s)

Current Resource Hints

preconnect
—
preload
—
dns-prefetch
1
prefetch
—

1 resource hints configured

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
A+
Green Hosting
Whether the site is served from green-energy infrastructure
PASS

Green Hosting

This site is hosted on green energy infrastructure

Provider: Google Cloud

A+
HTTP Caching
max-age=300 (5 minutes)
PASS
max-age=300 (5 minutes)
Info::
Cache-Control header is set
Got: max-age=300,public,max-age=300,public
Info::
Effective TTL: 5 minutes (max-age=300)
Info::
Last-Modified header present
Cache-Control

max-age=300,public,max-age=300,public

DirectiveValueMeaning
max-age300Cache for 5 minutes
public—Any cache may store this response
max-age300Cache for 5 minutes
public—Any cache may store this response
Effective TTL: 300 seconds
Network Waterfall
29 requests over 413ms
INFO
0 ms 1.0 s 2.0 s 3.0 s 4.0 s FCP 1.8 s LCP 4.7 shttps://krebsonsecurity.com// https://krebsonsecurity.com/ — 200 — 24.1 KiB — 76 ms — h2https://krebsonsecurity.com/wp-content/plugins/jquery-lightbox-for-native-galleries/colorbox/theme1/colorbox.css?ver=1.3.14/wp-content/plugins/jquery-lightbox... https://krebsonsecurity.com/wp-content/plugins/jquery-lightbox-for-native-galleries/colorbox/theme1/colorbox.css?ver=1.3.14 — 200 — 1.3 KiB — 32 ms — h2https://krebsonsecurity.com/wp-includes/css/dist/block-library/style.min.css?ver=6.2.2/wp-includes/css/dist/block-library... https://krebsonsecurity.com/wp-includes/css/dist/block-library/style.min.css?ver=6.2.2 — 200 — 12.5 KiB — 34 ms — h2https://krebsonsecurity.com/wp-includes/css/classic-themes.min.css?ver=6.2.2/wp-includes/css/classic-themes.min... https://krebsonsecurity.com/wp-includes/css/classic-themes.min.css?ver=6.2.2 — 200 — 270 B — 29 ms — h2https://krebsonsecurity.com/wp-content/plugins/contact-form-7/includes/css/styles.css?ver=5.8.2/wp-content/plugins/contact-form-7/... https://krebsonsecurity.com/wp-content/plugins/contact-form-7/includes/css/styles.css?ver=5.8.2 — 200 — 1.1 KiB — 29 ms — h2https://krebsonsecurity.com/wp-content/themes/kos-mar2021/style.css?subver=1.2&ver=6.2.2/wp-content/themes/kos-mar2021/styl... https://krebsonsecurity.com/wp-content/themes/kos-mar2021/style.css?subver=1.2&ver=6.2.2 — 200 — 10.9 KiB — 31 ms — h2https://krebsonsecurity.com/wp-content/themes/kos-mar2021/custom.css?subver=1.2&ver=6.2.2/wp-content/themes/kos-mar2021/cust... https://krebsonsecurity.com/wp-content/themes/kos-mar2021/custom.css?subver=1.2&ver=6.2.2 — 200 — 1.1 KiB — 32 ms — h2https://krebsonsecurity.com/wp-content/themes/kos-mar2021/fonts/font-awesome.min.css?ver=6.2.2/wp-content/themes/kos-mar2021/font... https://krebsonsecurity.com/wp-content/themes/kos-mar2021/fonts/font-awesome.min.css?ver=6.2.2 — 200 — 6.6 KiB — 34 ms — h2https://fonts.googleapis.com/css?family=Roboto%3Aregular%2Citalic%2C500%26subset%3Dlatin%2Cfonts.googleapis.com/css?family=Rob... https://fonts.googleapis.com/css?family=Roboto%3Aregular%2Citalic%2C500%26subset%3Dlatin%2C — 200 — 2.2 KiB — 81 ms — h2https://krebsonsecurity.com/wp-includes/js/jquery/jquery.min.js?ver=3.6.4/wp-includes/js/jquery/jquery.min.j... https://krebsonsecurity.com/wp-includes/js/jquery/jquery.min.js?ver=3.6.4 — 200 — 30.4 KiB — 44 ms — h2https://krebsonsecurity.com/wp-includes/js/jquery/jquery-migrate.min.js?ver=3.4.0/wp-includes/js/jquery/jquery-migra... https://krebsonsecurity.com/wp-includes/js/jquery/jquery-migrate.min.js?ver=3.4.0 — 200 — 4.7 KiB — 45 ms — h2https://krebsonsecurity.com/wp-content/plugins/jquery-lightbox-for-native-galleries/colorbox/jquery.colorbox-min.js?ver=1.3.14/wp-content/plugins/jquery-lightbox... https://krebsonsecurity.com/wp-content/plugins/jquery-lightbox-for-native-galleries/colorbox/jquery.colorbox-min.js?ver=1.3.14 — 200 — 4.0 KiB — 46 ms — h2https://krebsonsecurity.com/wp-content/plugins/jspullquotes/resources/jspullquotes-core.css/wp-content/plugins/jspullquotes/re... https://krebsonsecurity.com/wp-content/plugins/jspullquotes/resources/jspullquotes-core.css — 200 — 568 B — 33 ms — h2https://krebsonsecurity.com/wp-content/plugins/jspullquotes/resources/jspullquotes-default.css/wp-content/plugins/jspullquotes/re... https://krebsonsecurity.com/wp-content/plugins/jspullquotes/resources/jspullquotes-default.css — 200 — 441 B — 34 ms — h2https://krebsonsecurity.com/wp-content/plugins/jspullquotes/resources/jspullquotes.js/wp-content/plugins/jspullquotes/re... https://krebsonsecurity.com/wp-content/plugins/jspullquotes/resources/jspullquotes.js — 200 — 2.2 KiB — 44 ms — h2https://krebsonsecurity.com/b-doppel/13.png/b-doppel/13.png https://krebsonsecurity.com/b-doppel/13.png — 200 — 100.7 KiB — 105 ms — h2https://krebsonsecurity.com/b-keeper/18.png/b-keeper/18.png https://krebsonsecurity.com/b-keeper/18.png — 200 — 33.2 KiB — 95 ms — h2https://krebsonsecurity.com/wp-content/uploads/2021/03/kos-27-03-2021.jpg/wp-content/uploads/2021/03/kos-27-... https://krebsonsecurity.com/wp-content/uploads/2021/03/kos-27-03-2021.jpg — 200 — 82.1 KiB — 93 ms — h3https://krebsonsecurity.com/wp-content/uploads/2026/04/dailymail-tylerb.png/wp-content/uploads/2026/04/dailyma... https://krebsonsecurity.com/wp-content/uploads/2026/04/dailymail-tylerb.png — 200 — 348.4 KiB — 134 ms — h3https://krebsonsecurity.com/b-doppel/16.png/b-doppel/16.png https://krebsonsecurity.com/b-doppel/16.png — 200 — 71.3 KiB — 60 ms — h3https://krebsonsecurity.com/wp-content/themes/kos-mar2021/js/slicknav.js?ver=6.2.2/wp-content/themes/kos-mar2021/js/s... https://krebsonsecurity.com/wp-content/themes/kos-mar2021/js/slicknav.js?ver=6.2.2 — 200 — 4.0 KiB — 23 ms — h3https://krebsonsecurity.com/b-doppel/15.png/b-doppel/15.png https://krebsonsecurity.com/b-doppel/15.png — 200 — 82.2 KiB — 110 ms — h3https://krebsonsecurity.com/wp-content/uploads/2021/07/windupate-768x541.png/wp-content/uploads/2021/07/windupa... https://krebsonsecurity.com/wp-content/uploads/2021/07/windupate-768x541.png — 200 — 639.7 KiB — 176 ms — h3https://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 — 52 ms — h3https://fonts.gstatic.com/s/roboto/v51/KFOKCnqEu92Fr1Mu53ZEC9_Vu3r1gIhOszmOClHrs6ljXfMMLoHQuAj-k3Yk128.woff2fonts.gstatic.com/s/roboto/v51/KFOK... https://fonts.gstatic.com/s/roboto/v51/KFOKCnqEu92Fr1Mu53ZEC9_Vu3r1gIhOszmOClHrs6ljXfMMLoHQuAj-k3Yk128.woff2 — 200 — 17.8 KiB — 51 ms — h3https://krebsonsecurity.com/wp-content/themes/kos-mar2021/fonts/fontawesome-webfont.woff2?v=4.6.3/wp-content/themes/kos-mar2021/font... https://krebsonsecurity.com/wp-content/themes/kos-mar2021/fonts/fontawesome-webfont.woff2?v=4.6.3 — 200 — 70.2 KiB — 34 ms — h3https://fonts.gstatic.com/s/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMaxKUBHMdazTgWw.woff2fonts.gstatic.com/s/roboto/v51/KFO7... https://fonts.gstatic.com/s/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMaxKUBHMdazTgWw.woff2 — 200 — 16.3 KiB — 47 ms — h3https://fonts.gstatic.com/s/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMawCUBHMdazTgWw.woff2fonts.gstatic.com/s/roboto/v51/KFO7... https://fonts.gstatic.com/s/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMawCUBHMdazTgWw.woff2 — 200 — 35.5 KiB — 26 ms — h3https://krebsonsecurity.com/favicon.ico/favicon.ico https://krebsonsecurity.com/favicon.ico — 200 — 336 B — 20 ms — h3
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
23% of JavaScript execution is third-party
First-party Third-party 173ms · 0KB · $2/mo
Unattributable
Other
Optional
Execution 173ms
Transfer 0 KB
Monthly Cost $2/mo

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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