Performance
· 15 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.Performance-focused optimization plan with CWV assessment, top offenders, and time estimates
First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.
677 ms
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
1.82 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
11 ms
Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.
0.006
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
1.30 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.
2.45 s
Page Load Progression
DThird-Party ImpactAction100% third-party, 0 ms blockingFIX
DPage Weight InventoryAction58 resources · 2.0 MB · 286 KB savings availableFIX
~285.5 KiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 58 resources | 2.0 MiB | ||||||
FHTTP CachingActionNo cache headersFIX
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
CPage Weight BudgetAction2.0 MB transferred, 58 requestsREVIEW
Subset fonts to include only used characters, or switch to system font stacks.
Font payload is large — subset to used glyphs only, or fall back to system fonts (zero load time).
Source: web.dev font loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
JavaScript bundle is large — code-split routes and lazy-load off-screen components to defer.
Source: web.dev
CImage OptimizationAction24 images, 0 KB saveableREVIEW
Set explicit width and height to prevent CLS.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
BJS Execution Cost655ms total JS executionREVIEW
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://www.nsc.org/ | 194ms | 56ms | 1ms | 3rd |
| Unattributable | 124ms | 31ms | 0ms | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-T4SPTL | 76ms | 60ms | 13ms | 3rd |
| https://www.nsc.org/Content/generated/nsc.bundle.fda99dc6666dac98cd35.js | 76ms | 60ms | 11ms | 3rd |
| https://cdn.cookielaw.org/scripttemplates/202510.2.0/otBannerSdk.js | 74ms | 49ms | 16ms | 3rd |
| https://www.googletagmanager.com/gtag/destination?id=AW-1004748481&cx=c>m=4e64k0 | 56ms | 46ms | 9ms | 3rd |
| https://www.nsc.org/cdn-cgi/challenge-platform/scripts/jsd/main.js | 55ms | 53ms | 1ms | 3rd |
CJS BundlesAction11 scripts, 286 KB unusedREVIEW
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://www.nsc.org/Content/generated/nsc.bundle.fda99dc6666dac98cd35.js | 121 KB | 84 KB (70%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-T4SPTL | 173 KB | 75 KB (44%) | ✓ | 3rd |
| https://cdn.cookielaw.org/scripttemplates/202510.2.0/otBannerSdk.js | 124 KB | 65 KB (53%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtag/destination?id=AW-1004748481&cx=c>m=4e64k0 | 148 KB | 61 KB (41%) | ✓ | 3rd |
| https://kit.fontawesome.com/b85f2a5bf4.js | 6 KB | — | ✓ | 3rd |
| https://www.nsc.org/Content/generated/nsc.bundle.fda99dc6666dac98cd35.js.LICENSE.txt | 4 KB | — | ✗ | 3rd |
| https://static.cloudflareinsights.com/beacon.min.js/v8c78df7c7c0f484497ecbca7046644da1771523124516 | 11 KB | — | ✓ | 3rd |
| https://ka-p.fontawesome.com/releases/v5.15.4/js/pro-v4-shims.min.js?token=b85f2a5bf4 | 4 KB | — | ✓ | 3rd |
| https://ka-p.fontawesome.com/releases/v5.15.4/js/pro.min.js?token=b85f2a5bf4 | 14 KB | — | ✓ | 3rd |
| https://www.nsc.org/cdn-cgi/challenge-platform/h/b/scripts/jsd/0b8fb825cb67/main.js? | 12 KB | — | ✓ | 3rd |
Consider code splitting or tree shaking to reduce unused code.
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.
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.
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.
This bundle has high unused code — code-split or tree-shake to ship only what executes.
Source: web.dev / Lighthouse coverage
A+Text CompressionAll text resources are compressedPASS
A+Font Loading4 fonts (712 KB)PASS
Web fonts
4
712 KB total
Render-blocking
0
of 4
Dominant font-display
swap
Most common across fonts
Font loading timeline
- Convert to woff2 for ~30% smaller file size
- Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
- Convert to woff2 for ~30% smaller file size
- Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
- Convert to woff2 for ~30% smaller file size
- Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
- Convert to woff2 for ~30% smaller file size
- 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 ~569 KB and ~1138 ms
A+Resource CachingAll resources properly cachedPASS
A+Critical Rendering PathNo render-blocking resourcesPASS
A+Resource HintsNo optimization neededPASS
A+Green HostingWhether the site is served from green-energy infrastructurePASS
Green Hosting
This site is hosted on green energy infrastructure
Provider: Cloudflare
Network Waterfall58 requests over 1729msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
www.nsc.org www.nsc.org | Other | 194ms | 16 KB | — | $3/mo | Optional |
Unattributable Unattributable | Other | 124ms | 0 KB | — | $2/mo | Optional |
Google Tag Manager www.googletagmanager.com | Tag Manager | 76ms | 173 KB | 44% | $1/mo | Optional |
www.nsc.org www.nsc.org | Other | 76ms | 121 KB | 70% | $1/mo | Optional |
OneTrust cdn.cookielaw.org | Consent | 74ms | 124 KB | 53% | $1/mo | Essential |
Google Tag Manager www.googletagmanager.com | Tag Manager | 56ms | 148 KB | 41% | $1/mo | Optional |
www.nsc.org www.nsc.org | Other | 55ms | 0 KB | — | $1/mo | Optional |
100% of JavaScript execution time is spent on third-party scripts. Consider auditing which scripts are essential.
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
70% of www.nsc.org's code is unused. The script may be loading features you don't use.
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev
53% of OneTrust's code is unused. The script may be loading features you don't use.
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev