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.
4.93 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
31.34 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
3.82 s
Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.
0.931
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
7.95 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.
32.37 s
Page Load Progression
FPage Weight BudgetAction4.7 MB transferred, 132 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
Remove unused CSS rules with tools like PurgeCSS to reduce stylesheet size.
CSS bundle is large — purge unused styles (PurgeCSS, Tailwind JIT) to reduce CSS payload.
Source: web.dev
Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.
High HTTP request count — bundling, sprite-ing, and HTTP/2 server push can reduce per-request overhead.
Source: web.dev
DThird-Party ImpactAction100% third-party, 0 ms blockingFIX
FJS Execution CostAction9402ms total JS executionFIX
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://www.heart.org/dist/common/app.bundle.js?v=1.28.2.25892 | 1770ms | 1298ms | 215ms | 3rd |
| https://www.heart.org/ | 1499ms | 32ms | 5ms | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-5F7TTVL>m=4e64h1 | 801ms | 720ms | 65ms | 3rd |
| Unattributable | 754ms | 29ms | 0ms | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-PRLD9XQ | 547ms | 452ms | 68ms | 3rd |
| https://static.fundraiseup.com/7449.d9966e86b20cdf9f.js | 423ms | 355ms | 2ms | 3rd |
| https://cdn.cookielaw.org/scripttemplates/202601.2.0/otBannerSdk.js | 380ms | 211ms | 42ms | 3rd |
| https://cdn.optimizely.com/js/25670000279.js | 340ms | 275ms | 27ms | 3rd |
| https://cdn.fundraiseup.com/widget/ARMPCVPV | 289ms | 221ms | 23ms | 3rd |
| https://www.heart.org/dist/common/vendor.bundle.js?v=1.28.2.25892 | 288ms | 16ms | 260ms | 3rd |
Showing top 10 of 26 scripts
FJS BundlesAction61 scripts, 2.1 MB unusedFIX
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://www.heart.org/dist/common/app.bundle.js?v=1.28.2.25892 | 585 KB | 443 KB (76%) | ✓ | 3rd |
| https://static.fundraiseup.com/checkout.9e2624d0be733d7f.js | 410 KB | 366 KB (89%) | ✓ | 3rd |
| https://www.heart.org/dist/common/vendor.bundle.js?v=1.28.2.25892 | 484 KB | 332 KB (71%) | ✓ | 3rd |
| https://static.fundraiseup.com/checkout-sentry-vendor.dda4c7629502a974.js | 112 KB | 112 KB (100%) | ✓ | 3rd |
| https://static.cloud.coveo.com/searchui/v2.10116/js/CoveoJsSearch.Lazy.min.js | 211 KB | 104 KB (51%) | ✓ | 3rd |
| https://static.fundraiseup.com/checkout-vendors.78ab7844d94042df.js | 105 KB | 87 KB (83%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtag/js?id=G-JXBJ0MK9EJ&cx=c>m=4e64h1 | 168 KB | 77 KB (46%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-5F7TTVL>m=4e64h1 | 190 KB | 72 KB (38%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtag/js?id=UA-12551341-7 | 116 KB | 72 KB (62%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-PRLD9XQ | 187 KB | 71 KB (38%) | ✓ | 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
FPage Weight InventoryAction132 resources · 4.7 MB · 2.1 MB savings availableFIX
~2.1 MiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 132 resources | 4.7 MiB | ||||||
FHTTP CachingActionNo cache headersFIX
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
CImage OptimizationAction33 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
A+Text CompressionAll text resources are compressedPASS
A+Font Loading2 fonts (38 KB)PASS
Web fonts
2
38 KB total
Render-blocking
0
of 2
Dominant font-display
swap
Most common across fonts
Font loading timeline
- 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 ~1 KB and ~2 ms
A+Resource CachingAll resources properly cachedPASS
A+Critical Rendering PathNo render-blocking resourcesPASS
A+Resource Hints6 hints, 0 missing preconnectsPASS
Current Resource Hints
6 resource hints configured
A+Render-Blocking ResourcesNo render-blocking resources detectedPASS
A+Third-Party ResourcesNo third-party resources detectedPASS
A+Green HostingWhether the site is served from green-energy infrastructurePASS
Green Hosting
This site is hosted on green energy infrastructure
Provider: Cloudflare
Network Waterfall132 requests over 4200msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
www.heart.org www.heart.org | Other | 1770ms | 585 KB | 76% | €31/mo | Costly |
www.heart.org www.heart.org | Other | 1499ms | 28 KB | — | €26/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 801ms | 190 KB | 38% | €14/mo | Costly |
Unattributable Unattributable | Other | 754ms | 0 KB | — | €13/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 547ms | 187 KB | 38% | €9/mo | Costly |
static.fundraiseup.com static.fundraiseup.com | Other | 423ms | 7 KB | — | €7/mo | Costly |
OneTrust cdn.cookielaw.org | Consent | 380ms | 128 KB | 53% | €7/mo | Essential |
Optimizely cdn.optimizely.com | A/B Testing | 340ms | 103 KB | 41% | €6/mo | Costly |
cdn.fundraiseup.com cdn.fundraiseup.com | Other | 289ms | 76 KB | 30% | €5/mo | Costly |
www.heart.org www.heart.org | Other | 288ms | 484 KB | 71% | €5/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 259ms | 145 KB | 43% | €5/mo | Costly |
static.fundraiseup.com static.fundraiseup.com | Other | 259ms | 105 KB | 83% | €4/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 245ms | 168 KB | 46% | €4/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 206ms | 129 KB | 47% | €4/mo | Costly |
static.cloud.coveo.com static.cloud.coveo.com | Other | 199ms | 211 KB | 51% | €3/mo | Optional |
Google Tag Manager www.googletagmanager.com | Tag Manager | 194ms | 129 KB | 48% | €3/mo | Optional |
static.fundraiseup.com static.fundraiseup.com | Other | 164ms | 410 KB | 89% | €3/mo | Optional |
Google Tag Manager www.googletagmanager.com | Tag Manager | 159ms | 129 KB | 48% | €3/mo | Optional |
static.cloud.coveo.com static.cloud.coveo.com | Other | 97ms | 22 KB | — | €2/mo | Optional |
static.cloud.coveo.com static.cloud.coveo.com | Other | 93ms | 12 KB | — | €2/mo | Optional |
OneTrust cdn.cookielaw.org | Consent | 80ms | 9 KB | — | €1/mo | Essential |
Google Tag Manager www.googletagmanager.com | Tag Manager | 78ms | 116 KB | 62% | €1/mo | Optional |
static.cloud.coveo.com static.cloud.coveo.com | Other | 77ms | 1 KB | — | €1/mo | Optional |
static.fundraiseup.com static.fundraiseup.com | Other | 71ms | 140 KB | — | €1/mo | Optional |
www.heart.org www.heart.org | Other | 71ms | 39 KB | 55% | €1/mo | Optional |
static.fundraiseup.com static.fundraiseup.com | Other | 58ms | 37 KB | — | €1/mo | Optional |
These scripts may cost more than they're worth
- www.heart.org adds 1770ms and costs ~€31/month
- www.heart.org adds 1499ms and costs ~€26/month
- Google Tag Manager adds 801ms and costs ~€14/month
- Unattributable adds 754ms and costs ~€13/month
- Google Tag Manager adds 547ms and costs ~€9/month
- static.fundraiseup.com adds 423ms and costs ~€7/month
- Optimizely adds 340ms and costs ~€6/month
- cdn.fundraiseup.com adds 289ms and costs ~€5/month
- www.heart.org adds 288ms and costs ~€5/month
- Google Tag Manager adds 259ms and costs ~€5/month
- static.fundraiseup.com adds 259ms and costs ~€4/month
- Google Tag Manager adds 245ms and costs ~€4/month
- Google Tag Manager adds 206ms and costs ~€4/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
www.heart.org takes 1770ms 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
76% of www.heart.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
www.heart.org takes 1499ms 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 801ms 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 754ms 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 547ms 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
static.fundraiseup.com takes 423ms 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
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
Optimizely takes 340ms 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
cdn.fundraiseup.com takes 289ms 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.heart.org takes 288ms 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
71% of www.heart.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
Google Tag Manager takes 259ms 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
static.fundraiseup.com takes 259ms 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
83% of static.fundraiseup.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
Google Tag Manager takes 245ms 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 206ms 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
51% of static.cloud.coveo.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
89% of static.fundraiseup.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
62% of Google Tag Manager'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
55% of www.heart.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