Performance
· 17 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.
10.70 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
18.54 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
824 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.
10.70 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.
18.68 s
Page Load Progression
DPage Weight BudgetAction2.6 MB transferred, 88 requestsFIX
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
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
DThird-Party ImpactAction100% third-party, 0 ms blockingFIX
DJS Execution CostAction3275ms total JS executionFIX
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://www.googletagmanager.com/gtm.js?id=GTM-MBL5BT2 | 619ms | 510ms | 32ms | 3rd |
| https://www.googletagmanager.com/gtag/js?id=G-CY2GPTVZY7&cx=c>m=4e64k1 | 425ms | 355ms | 37ms | 3rd |
| Unattributable | 394ms | 65ms | 0ms | 3rd |
| https://www.calpoly.edu/sites/default/files/js/js_FdenDZp-2hBySUCqDqfP-aGLtsElf0FUdLF158oObQU.js?scope=footer&delta=0&language=en&theme=calpoly_v2&include=eJxtyVEOgzAMA9ALoVbahZChJcuWNYgG2t5--0ATsP1Y9jNCMEVqHntx06LJuhEyq7R-0jUFGGvyJDpAvs92-yNaxI1YdM3x5Flg0c1cr8zj8wecMN1t0Hp8Ns5sAS0fsWjpSJUk9gby9InrdnignvH1BosAXkg | 364ms | 256ms | 9ms | 3rd |
| https://www.calpoly.edu/ | 318ms | 6ms | 1ms | 3rd |
| https://www.calpoly.edu/sites/default/files/js/js_9NwcSgdGsm9DObnpkCuS0bYjMMRLPEbOwaTtfs3BLsg.js?scope=footer&delta=2&language=en&theme=calpoly_v2&include=eJxtyVEOgzAMA9ALoVbahZChJcuWNYgG2t5--0ATsP1Y9jNCMEVqHntx06LJuhEyq7R-0jUFGGvyJDpAvs92-yNaxI1YdM3x5Flg0c1cr8zj8wecMN1t0Hp8Ns5sAS0fsWjpSJUk9gby9InrdnignvH1BosAXkg | 298ms | 51ms | 23ms | 3rd |
| https://www.googletagmanager.com/gtag/js?id=G-Z6VS956HHF&cx=c>m=4e64k1 | 243ms | 206ms | 35ms | 3rd |
| https://analytics.tiktok.com/i18n/pixel/static/main.MWE0ZWQ3ZWQwMA.js | 189ms | 149ms | 38ms | 3rd |
| https://connect.facebook.net/signals/config/1071644058215938?v=2.9.303&r=stable&domain=www.calpoly.edu&hme=97937018cefade17726f0472876fc101316b2ce9008a35a6a5a7977d7436151a&ex_m=104%2C205%2C154%2C22%2C72%2C73%2C145%2C68%2C67%2C11%2C162%2C90%2C16%2C138%2C127%2C39%2C75%2C78%2C134%2C159%2C164%2C8%2C4%2C5%2C7%2C6%2C3%2C91%2C101%2C165%2C170%2C219%2C62%2C186%2C187%2C55%2C276%2C30%2C74%2C231%2C230%2C229%2C23%2C33%2C103%2C61%2C10%2C63%2C97%2C98%2C99%2C105%2C130%2C31%2C29%2C132%2C133%2C129%2C128%2C155%2C76%2C158%2C156%2C157%2C50%2C60%2C123%2C15%2C161%2C45%2C263%2C264%2C262%2C26%2C27%2C28%2C48%2C146%2C77%2C112%2C18%2C20%2C44%2C40%2C42%2C41%2C83%2C92%2C96%2C110%2C144%2C147%2C46%2C111%2C24%2C21%2C119%2C69%2C36%2C149%2C148%2C150%2C141%2C139%2C25%2C35%2C59%2C109%2C160%2C70%2C17%2C152%2C114%2C81%2C66%2C19%2C85%2C86%2C116%2C84%2C136%2C135%2C34%2C278%2C293%2C212%2C201%2C202%2C200%2C296%2C288%2C52%2C213%2C107%2C131%2C80%2C121%2C54%2C47%2C49%2C113%2C120%2C126%2C58%2C64%2C151%2C115%2C37%2C32%2C53%2C56%2C100%2C163%2C1%2C124%2C14%2C122%2C12%2C2%2C57%2C93%2C65%2C118%2C89%2C88%2C166%2C167%2C94%2C95%2C9%2C125%2C102%2C51%2C142%2C87%2C79%2C71%2C117%2C106%2C43%2C143%2C0%2C82%2C137%2C140%2C153%2C38%2C108%2C13%2C168 | 127ms | 105ms | 22ms | 3rd |
| https://connect.facebook.net/en_US/fbevents.js | 121ms | 90ms | 30ms | 3rd |
Showing top 10 of 12 scripts
DJS BundlesAction29 scripts, 369 KB unusedFIX
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://www.googletagmanager.com/gtag/js?id=G-CY2GPTVZY7&cx=c>m=4e64k1 | 172 KB | 68 KB (39%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtag/js?id=G-Z6VS956HHF&cx=c>m=4e64k1 | 157 KB | 65 KB (41%) | ✓ | 3rd |
| https://www.calpoly.edu/sites/default/files/js/js_9NwcSgdGsm9DObnpkCuS0bYjMMRLPEbOwaTtfs3BLsg.js?scope=footer&delta=2&language=en&theme=calpoly_v2&include=eJxtyVEOgzAMA9ALoVbahZChJcuWNYgG2t5--0ATsP1Y9jNCMEVqHntx06LJuhEyq7R-0jUFGGvyJDpAvs92-yNaxI1YdM3x5Flg0c1cr8zj8wecMN1t0Hp8Ns5sAS0fsWjpSJUk9gby9InrdnignvH1BosAXkg | 92 KB | 63 KB (69%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-MBL5BT2 | 140 KB | 61 KB (43%) | ✓ | 3rd |
| https://analytics.tiktok.com/i18n/pixel/static/main.MWE0ZWQ3ZWQwMA.js | 106 KB | 57 KB (54%) | ✓ | 3rd |
| https://connect.facebook.net/en_US/fbevents.js | 97 KB | 34 KB (36%) | ✓ | 3rd |
| https://static.addtoany.com/menu/modules/core.ydpp7jcu.js | 26 KB | 21 KB (82%) | ✓ | 3rd |
| https://mx.technolutions.net/ping?id=4e2b48d3-a5fc-fabe-30f1-c1a95714e84d&sid=ISoaykiDL1Sl23L3usQqQjnUPirjPPdJLuMNMSG6ADq-wPYJaYqXUfoQwej2gNcWvpQffFZu34TU0z_hhIE-cOMAeg5f8oP8djVHmsQ9YoNbUeOR04GfyAzBysjevVc-&hid=197dd5ce-037d-aaa8-ce4e-97fda6636e5a | 4 KB | — | ✓ | 3rd |
| https://acdn.adnxs.com/dmp/up/pixie.js | 9 KB | — | ✓ | 3rd |
| https://cdnjs.cloudflare.com/ajax/libs/wow/1.1.2/wow.min.js | 3 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
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
DPage Weight InventoryAction88 resources · 2.6 MB · 369 KB savings availableFIX
~368.6 KiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 88 resources | 2.6 MiB | ||||||
FHTTP CachingActionNo cache headersFIX
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
BImage Optimization14 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
CGreen HostingActionWhether the site is served from green-energy infrastructureREVIEW
Green Hosting
No green hosting detected
A+Text CompressionAll text resources are compressedPASS
A+Font Loading9 fonts (728 KB)PASS
Web fonts
9
728 KB total
Render-blocking
0
of 9
Dominant font-display
swap
Most common across fonts
Font loading timeline
- Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
- Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
- 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 ~248 KB and ~496 ms
A+Resource CachingAll resources properly cachedPASS
A+Critical Rendering PathNo render-blocking resourcesPASS
A+Resource HintsNo optimization neededPASS
A+Render-Blocking ResourcesNo render-blocking resources detectedPASS
A+Third-Party ResourcesNo third-party resources detectedPASS
Network Waterfall88 requests over 3219msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
Google Tag Manager www.googletagmanager.com | Tag Manager | 619ms | 140 KB | 43% | €7/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 425ms | 172 KB | 39% | €5/mo | Costly |
Unattributable Unattributable | Other | 394ms | 0 KB | — | €4/mo | Costly |
www.calpoly.edu www.calpoly.edu | Other | 364ms | 40 KB | — | €4/mo | Costly |
www.calpoly.edu www.calpoly.edu | Other | 318ms | 18 KB | — | €3/mo | Costly |
www.calpoly.edu www.calpoly.edu | Other | 298ms | 92 KB | 69% | €3/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 243ms | 157 KB | 41% | €3/mo | Costly |
analytics.tiktok.com analytics.tiktok.com | Other | 189ms | 106 KB | 54% | €2/mo | Optional |
Facebook Pixel connect.facebook.net | Advertising | 127ms | 45 KB | — | €1/mo | Optional |
Facebook Pixel connect.facebook.net | Advertising | 121ms | 97 KB | 36% | €1/mo | Optional |
sc-static.net sc-static.net | Other | 115ms | 25 KB | — | €1/mo | Optional |
www.calpoly.edu www.calpoly.edu | Other | 62ms | 107 KB | — | €1/mo | Optional |
These scripts may cost more than they're worth
- Google Tag Manager adds 619ms and costs ~€7/month
- Google Tag Manager adds 425ms and costs ~€5/month
- Unattributable adds 394ms and costs ~€4/month
- www.calpoly.edu adds 364ms and costs ~€4/month
- www.calpoly.edu adds 318ms and costs ~€3/month
- www.calpoly.edu adds 298ms and costs ~€3/month
- Google Tag Manager adds 243ms and costs ~€3/month
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
Google Tag Manager takes 619ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
Google Tag Manager takes 425ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
Unattributable takes 394ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
www.calpoly.edu takes 364ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
www.calpoly.edu takes 318ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
www.calpoly.edu takes 298ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
69% of www.calpoly.edu'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
Google Tag Manager takes 243ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
54% of analytics.tiktok.com'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