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.
3.41 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
3.41 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
341 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.
5.18 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.
9.78 s
Page Load Progression
DThird-Party ImpactAction100% third-party, 0 ms blockingFIX
DPage Weight InventoryAction59 resources · 1.4 MB · 291 KB savings availableFIX
~291.2 KiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 59 resources | 1.4 MiB | ||||||
FHTTP CachingActionNo cache headersFIX
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
BPage Weight Budget1.4 MB transferred, 59 requestsREVIEW
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
BImage Optimization4 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
CJS Execution CostAction1504ms total JS executionREVIEW
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://www.ontario.ca/18f5227b-e27b-445a-a53f-f845fbe69b40/stormcaster.js | 345ms | 269ms | 29ms | 3rd |
| https://www.ontario.ca/libraries/ontario-search-autosuggest/dist/index.js?v=1.x | 299ms | 234ms | 57ms | 3rd |
| https://www.googletagmanager.com/gtag/js?id=G-HLLEK4SB6V&cx=c>m=4e64h1 | 262ms | 219ms | 40ms | 3rd |
| Unattributable | 211ms | 7ms | 0ms | 3rd |
| https://www.ontario.ca/ | 132ms | 7ms | 2ms | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-KZMGBJD | 123ms | 94ms | 28ms | 3rd |
| https://www.ontario.ca/themes/ontario_2021/css/ontario2021-theme.css?tdlsdl | 79ms | 0ms | 0ms | 3rd |
| https://www.ontario.ca/core/misc/drupal.init.js?v=10.5.9 | 54ms | 42ms | 0ms | 3rd |
CJS BundlesAction39 scripts, 291 KB unusedREVIEW
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://www.ontario.ca/libraries/ontario-search-autosuggest/dist/index.js?v=1.x | 262 KB | 102 KB (40%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtag/js?id=G-HLLEK4SB6V&cx=c>m=4e64h1 | 169 KB | 65 KB (38%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-KZMGBJD | 131 KB | 62 KB (48%) | ✓ | 3rd |
| https://www.ontario.ca/18f5227b-e27b-445a-a53f-f845fbe69b40/stormcaster.js | 165 KB | 40 KB (24%) | ✓ | 3rd |
| https://www.ontario.ca/core/assets/vendor/jquery/jquery.min.js?v=3.7.1 | 35 KB | 22 KB (63%) | ✓ | 3rd |
| https://www.ontario.ca/themes/ontario_2021/js/onesite_language_cookie.js | 1 KB | — | ✓ | 3rd |
| https://www.ontario.ca/themes/ontario_2021/design_system/scripts/back-to-top.js?tdlsdl | 1 KB | — | ✓ | 3rd |
| https://www.ontario.ca/core/assets/vendor/tabbable/index.umd.min.js?v=6.2.0 | 3 KB | — | ✓ | 3rd |
| https://www.ontario.ca/core/misc/progress.js?v=10.5.9 | 2 KB | — | ✓ | 3rd |
| https://www.ontario.ca/core/assets/vendor/loadjs/loadjs.min.js?v=4.3.0 | 1 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
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 Loading4 fonts (42 KB)PASS
Web fonts
4
42 KB total
Render-blocking
0
of 4
Dominant font-display
swap
Most common across fonts
Font loading timeline
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)
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 Waterfall59 requests over 2067msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
www.ontario.ca www.ontario.ca | Other | 345ms | 165 KB | 24% | CA$5/mo | Costly |
www.ontario.ca www.ontario.ca | Other | 299ms | 262 KB | 40% | CA$4/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 262ms | 169 KB | 38% | CA$4/mo | Costly |
Unattributable Unattributable | Other | 211ms | 0 KB | — | CA$3/mo | Costly |
www.ontario.ca www.ontario.ca | Other | 132ms | 27 KB | — | CA$2/mo | Optional |
Google Tag Manager www.googletagmanager.com | Tag Manager | 123ms | 131 KB | 48% | CA$2/mo | Optional |
www.ontario.ca www.ontario.ca | Other | 79ms | 128 KB | — | CA$1/mo | Optional |
www.ontario.ca www.ontario.ca | Other | 54ms | 1 KB | — | CA$1/mo | Optional |
These scripts may cost more than they're worth
- www.ontario.ca adds 345ms and costs ~CA$5/month
- www.ontario.ca adds 299ms and costs ~CA$4/month
- Google Tag Manager adds 262ms and costs ~CA$4/month
- Unattributable adds 211ms and costs ~CA$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
www.ontario.ca takes 345ms 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.ontario.ca takes 299ms 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 262ms 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 211ms 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