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https://waterexamprep.com

Performance

· 26 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
94
GRADE
A
FIX
2
REVIEW
3
PASS
18
INFO
3

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

Mobile Desktop
73
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
100
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.
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.

3.87 s

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

4.63 s

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

16 ms

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.

4.87 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.

4.63 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
26
18 PASS 3 REVIEW 2 FIX
D
Third-Party Impact
Action
94% third-party, 0 ms blocking
FIX
94% third-party, 0 ms blocking
Warning::
Third-party code accounts for 94% of page weight (315.6 KiB of 337.4 KiB)
Info::
Third-party blocking time is low (0 ms)
94%
First-party Third-party
D
HTTP Caching
Action
no-store (uncacheable)
FIX
no-store (uncacheable)
Info::
Cache-Control: no-store prevents all caching
Intentional for dynamic content, but increases server load for every page view.
Got: no-store, no-cache, must-revalidate
Info::
No ETag or Last-Modified header
Conditional requests (304 Not Modified) are not possible without validators.
Cache-Control

no-store, no-cache, must-revalidate

DirectiveValueMeaning
no-store—Never cache this response
no-cache—Cache but always revalidate first
must-revalidate—Must recheck with server after expiry
B
JS Execution Cost
841ms total JS execution
REVIEW
841ms total JS execution
Warning::
https://www.googletagmanager.com/gtag/js?id=G-TRDF...: 362ms CPU time
Info::
https://www.googletagmanager.com/gtm.js?id=GTM-TTQ...: 185ms CPU time
Info::
https://waterexamprep.com/: 168ms CPU time
Info::
Unattributable: 126ms CPU time
Warning::
Third-party scripts: 547ms (65% of total)

Main Thread Breakdown

Script Evaluation 49% Style & Layout 20% Other 14% Script Parsing & Compilation 12%
ScriptTotalScriptingParse/CompileParty
https://www.googletagmanager.com/gtag/js?id=G-TRDF1R3E4Q&cx=c&gtm=4e6a61362ms250ms63ms3rd
https://www.googletagmanager.com/gtm.js?id=GTM-TTQSW79C185ms144ms36ms3rd
https://waterexamprep.com/168ms9ms3ms1st
Unattributable126ms7ms0ms1st
B
JS Bundles
2 scripts, 144 KB unused
REVIEW
2 scripts, 144 KB unused
Warning::
https://www.googletagmanager.com/gtag/js?id=G-TRDF...: 80 KB unused (42%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtm.js?id=GTM-TTQ...: 65 KB unused (52%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 144 KB
144 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.googletagmanager.com/gtag/js?id=G-TRDF1R3E4Q&cx=c&gtm=4e6a61190 KB80 KB (42%)✓3rd
https://www.googletagmanager.com/gtm.js?id=GTM-TTQSW79C125 KB65 KB (52%)✓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

B
Server-Timing Observability
No Server-Timing header found
REVIEW
No Server-Timing header found
Info::
No Server-Timing header found
Server-Timing exposes backend timing breakdowns to browser DevTools (e.g., `db: 45ms; render: 120ms; cache: 2ms`). Useful for diagnosing slow pages without backend log access. Most modern frameworks (Next.js, Cloudflare Workers, Fastly) emit it automatically; absence on a managed platform usually means telemetry headers are stripped at the edge.
A+
Page Weight Budget
337 KB transferred, 6 requests
PASS
337 KB transferred, 6 requests
Info::
Page weighs 1.0 MB (337 KB transferred)
Info::
6 HTTP requests
Info::
Estimated 0.07 g CO2 per page load
337 KB / 2.4 MB budget
337 KB transferred
6 requests
0.07 g CO2 per page load
JavaScript 315.1 KiB 93%
CSS 11.3 KiB 3%
HTML 6.6 KiB 2%
Other 3.7 KiB 1%
Other 549 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+
Image Optimization
No images on this page
PASS
No images on this page
Info::
No images on this page
0 images 0 KB
0 oversized -0 KB
0 legacy format
0 missing dimensions CLS risk
A+
Font Loading
No web fonts (system fonts)
PASS
No web fonts (system fonts)
Info::
No web fonts loaded — system fonts are fastest
No web fonts loaded — system fonts are optimal.
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+
HTTP/3 (QUIC)
HTTP/3 advertised via Alt-Svc
PASS
HTTP/3 advertised via Alt-Svc
Info::
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+
Document Compression
Document response uses brotli
PASS
Document response uses brotli
Info::
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
Info::
LCP image preload audit not available for this scan
A+
Main HTML Cache-Control
Main HTML uses no-store -- correct for sensitive/dynamic content
PASS
Main HTML uses no-store -- correct for sensitive/dynamic content
Info::
Main HTML uses no-store -- correct for sensitive/dynamic content
Got: no-store, no-cache, must-revalidate
A+
Server Response Intelligence
2 server-response signal(s) detected
PASS
2 server-response signal(s) detected
Info::
`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).
Info::
No `ETag` or `Last-Modified` -- conditional GET not supported
Without either header, browsers can't issue conditional GETs and refresh always re-downloads the full response body even when nothing changed. Add `ETag: "<hash>"` (or `Last-Modified: <date>`) on cacheable responses; the server returns 304 Not Modified when the client's cached copy is still valid, saving bandwidth.
A
Page Weight Inventory
6 resources · 337 KB · 144 KB savings available
PASS
6 resources · 337 KB · 144 KB savings available
Info::
Within 1MB page-weight target
Got: 337 KB
Info::
~144 KB of savings available
Warning::
3 third-party resources (94% of weight)
6 resources · 337.4 KiB · 3 third-party Within 1MB page-weight target
JavaScript 93% · 315.1 KiB
CSS 3% · 11.3 KiB
Document 3% · 10.4 KiB
Other 0% · 549 B

~144.3 KiB of savings available

Remove unused JavaScript: 144.3 KiB
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+
JavaScript Blocking
No render-blocking JS or document.write usage detected
PASS
No render-blocking JS or document.write usage detected
Info::
No JavaScript blocking issues detected
A+
CSS Performance Depth
No CSS performance depth issues detected
PASS
No CSS performance depth issues detected
Info::
No CSS performance depth issues 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: Cloudflare

Asset Compression
No text asset hosts to measure
INFO
No text asset hosts to measure
Info::
No third-party or subdomain host served enough text assets to measure
Asset compression is measured per host, from one HEAD request against a sampled resource. Pages that serve all their JS and CSS from the document's own origin are covered by the document compression check instead.
Network Waterfall
6 requests over 875ms
INFO
0 ms 1.0 s 2.0 s 3.0 s 4.0 s FCP 3.9 s LCP 4.6 shttps://waterexamprep.com// https://waterexamprep.com/ — 200 — 6.6 KiB — 179 ms — h2https://waterexamprep.com/assets/css/site.css?v=20260918-5/assets/css/site.css?v=20260918-5 https://waterexamprep.com/assets/css/site.css?v=20260918-5 — 200 — 11.3 KiB — 441 ms — h2https://www.googletagmanager.com/gtm.js?id=GTM-TTQSW79Cwww.googletagmanager.com/gtm.js?id=... https://www.googletagmanager.com/gtm.js?id=GTM-TTQSW79C — 200 — 125.2 KiB — 244 ms — h2https://www.googletagmanager.com/gtag/js?id=G-TRDF1R3E4Q&cx=c&gtm=4e6a61www.googletagmanager.com/gtag/js?id... https://www.googletagmanager.com/gtag/js?id=G-TRDF1R3E4Q&cx=c&gtm=4e6a61 — 200 — 189.9 KiB — 123 ms — h2https://region1.google-analytics.com/g/collect?v=2&tid=G-TRDF1R3E4Q&gtm=45je6a61v9264675274z89264651282za20gzb9264651282zd9264651282xf1&_p=1791467142105&gcs=G100&gcd=13p3p3p2p5l1&npa=1&dma_cps=-&dma=1&_eu=AAAAACAC&cid=2002075528.1791467143&frm=0&ibt=1&ngs=1&pscdl=denied&rcb=8&sr=412x823&uaa=&uab=64&uafvl=Not%2520A(Brand%3B99.0.0.0%7CChromium%3B154.0.8037.92&uam=moto%20g%20power%20(2022)&uamb=1&uap=Android&uapv=11.0&uaw=0&ul=en-us&_s=1&tag_exp=115938466~115938469~118897920~118897930~120213116~120385423~120469145~120469153~121046263~121046271~121280969&sid=1791467142&sct=1&seg=0&dl=https%3A%2F%2Fwaterexamprep.com%2F&dt=Water%20%26%20Wastewater%20Operator%20Exam%20Prep%20%7C%20WaterExamPrep&en=page_view&_fv=1&_nsi=1&_ss=1&tfd=694region1.google-analytics.com/g/coll... https://region1.google-analytics.com/g/collect?v=2&tid=G-TRDF1R3E4Q&gtm=45je6a61v9264675274z89264651282za20gzb9264651282zd9264651282xf1&_p=1791467142105&gcs=G100&gcd=13p3p3p2p5l1&npa=1&dma_cps=-&dma=1&_eu=AAAAACAC&cid=2002075528.1791467143&frm=0&ibt=1&ngs=1&pscdl=denied&rcb=8&sr=412x823&uaa=&uab=64&uafvl=Not%2520A(Brand%3B99.0.0.0%7CChromium%3B154.0.8037.92&uam=moto%20g%20power%20(2022)&uamb=1&uap=Android&uapv=11.0&uaw=0&ul=en-us&_s=1&tag_exp=115938466~115938469~118897920~118897930~120213116~120385423~120469145~120469153~121046263~121046271~121280969&sid=1791467142&sct=1&seg=0&dl=https%3A%2F%2Fwaterexamprep.com%2F&dt=Water%20%26%20Wastewater%20Operator%20Exam%20Prep%20%7C%20WaterExamPrep&en=page_view&_fv=1&_nsi=1&_ss=1&tfd=694 — 204 — 549 B — 88 ms — h2https://waterexamprep.com/favicon.ico/favicon.ico https://waterexamprep.com/favicon.ico — 404 — 3.7 KiB — 115 ms — h3
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
65% of JavaScript execution is third-party
First-party Third-party 547ms · 315KB · €6/mo
Google Tag Manager
Tag Manager
Costly
Execution 362ms
Transfer 190 KB
Unused 42%
Monthly Cost €4/mo
Google Tag Manager
Tag Manager
Optional
Execution 185ms
Transfer 125 KB
Unused 52%
Monthly Cost €2/mo

These scripts may cost more than they're worth

  • Google Tag Manager adds 362ms and costs ~€4/month

65% of JavaScript execution time comes from third-party scripts.

Why this matters

Third-party scripts (analytics, ads, social, A/B testing) often dominate execution time — every one is a perf-and-privacy tax.

Learn more ▾

Each third-party script is a black box: you don't control when it loads, what it executes, or how much it grows. They often account for a major share of total blocking time on average sites (HTTP Archive's Web Almanac documents the trend). Audit which ones you actually need, defer the rest, and use facade patterns (lite-youtube, lite-vimeo) for embedded media.

Source: web.dev / HTTP Archive Web Almanac

Google Tag Manager takes 362ms 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

52% 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

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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