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https://www.uottawa.ca

Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
75
GRADE
C
FIX
2
REVIEW
2
PASS
8
INFO
2

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

Mobile Desktop
75
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.
81
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
92
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.

965 ms

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

3.85 s

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

80 ms

Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.

0.024

Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.

1.83 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.

4.27 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
14
8 PASS 2 REVIEW 2 FIX
F
Page Weight Budget
Action
5.1 MB transferred, 99 requests
FIX
5.1 MB transferred, 99 requests
Critical::
Page weighs 8.4 MB (5.1 MB transferred)
Warning::
Images are 3.6 MB — compress or use modern formats
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
Got: 3.6 MB
Warning::
JavaScript is 1.1 MB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 1.1 MB
Info::
Fonts are 203 KB — consider subsetting or using system fonts
Subset fonts to include only used characters, or switch to system font stacks.
Got: 203 KB
Info::
99 HTTP requests
Info::
Estimated 1.1 g CO2 per page load
5.1 MB / 2.4 MB budget
5.1 MB transferred
99 requests
1.1 g CO2 per page load
Images 3.6 MiB 72%
JavaScript 1.1 MiB 22%
Fonts 203.3 KiB 4%
CSS 54.3 KiB 1%
HTML 26.7 KiB 1%
Other 6.7 KiB 0%
Other 5.2 KiB 0%
Other 3.1 KiB 0%
Other 2.1 KiB 0%
Other 0 B 0%
0 2.4 MB 4.9 MB
Over budget

Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.

Why this matters

Image bandwidth is high — modern formats (WebP/AVIF) and resizing typically cut it 50%+.

Source: web.dev

Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.

Why this matters

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.

Why this matters

Font payload is large — subset to used glyphs only, or fall back to system fonts (zero load time).

Source: web.dev font loading

D
JS Bundles
Action
38 scripts, 365 KB unused
FIX
38 scripts, 365 KB unused
Warning::
https://www.uottawa.ca/sites/g/files/bhrskd331/fil...: 70 KB unused (52%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtag/js?id=G-GKVJ...: 65 KB unused (36%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtm.js?id=GTM-WVK...: 62 KB unused (38%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtag/js?id=AW-873...: 61 KB unused (42%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://analytics.tiktok.com/i18n/pixel/static/mai...: 56 KB unused (51%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 365 KB
365 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.uottawa.ca/sites/g/files/bhrskd331/files/js/js_f6HUhyIqRKOI6LbMUIhd4AvYW3d-YV_AaD9LZR5k6yY.js?scope=footer&delta=2&language=en&theme=uottawa&include=eJx1kGtuwzAMgy_kzLuRIbuKy0V-wFbbpKevlwFpO2x_KOiTIBLyQvfNepQP-qLV8MWFUhbwKKkKKAd2UZP9b2BiKVHYKUUbh_zuf86-wWQwN0rsGnfcuVlkqNlzfIsR-EZtc52phbN9b4d9nhHdXFoyl6JKN7KBUiXEzO1AMwX2I_BUsbI8MdbdfBwLgXuHh0C317mSRz7x-vn3RpTiSaaumyDHA3coI9VWrvxkgrBMQ08vwXqmGs6kB1AseuS8gm_d7rp_7gFk_6Nb134 KB70 KB (52%)✓1st
https://www.googletagmanager.com/gtag/js?id=G-GKVJ53FL3H&cx=c&gtm=4e6460178 KB65 KB (36%)✓3rd
https://www.googletagmanager.com/gtm.js?id=GTM-WVKZFC165 KB62 KB (38%)✓3rd
https://www.googletagmanager.com/gtag/js?id=AW-873072808&cx=c&gtm=4e6460146 KB61 KB (42%)✓3rd
https://analytics.tiktok.com/i18n/pixel/static/main.MWE0ZWQ3ZWQwMQ.js110 KB56 KB (51%)✓3rd
https://connect.facebook.net/en_US/fbevents.js95 KB32 KB (34%)✓3rd
https://www.uottawa.ca/sites/g/files/bhrskd331/files/js/js_17DkJEeQQi8P3KAkWwSYqfUyECzXDD9xwODiqGixV2o.js?scope=footer&delta=0&language=en&theme=uottawa&include=eJx1kGtuwzAMgy_kzLuRIbuKy0V-wFbbpKevlwFpO2x_KOiTIBLyQvfNepQP-qLV8MWFUhbwKKkKKAd2UZP9b2BiKVHYKUUbh_zuf86-wWQwN0rsGnfcuVlkqNlzfIsR-EZtc52phbN9b4d9nhHdXFoyl6JKN7KBUiXEzO1AMwX2I_BUsbI8MdbdfBwLgXuHh0C317mSRz7x-vn3RpTiSaaumyDHA3coI9VWrvxkgrBMQ08vwXqmGs6kB1AseuS8gm_d7rp_7gFk_6Nb29 KB21 KB (73%)✓1st
https://analytics.tiktok.com/i18n/pixel/events.js?sdkid=C6OG9ERSVD35Q9TRJ990&lib=ttq3 KB—✓3rd
https://www.uottawa.ca/modules/contrib/google_tag/js/gtm.js?tci2ce1 KB—✓1st
https://www.uottawa.ca/themes/custom/uottawa/src/js/lib/tiktok-pixel.js?tci2ce1 KB—✓1st

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

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

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

C
Image Optimization
Action
20 images, 0 KB saveable
REVIEW
20 images, 0 KB saveable
Warning::
https://www.uottawa.ca/themes/custom/uottawa/dist/... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.uottawa.ca/themes/custom/uottawa/dist/... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
20 images 3.6 MB
0 oversized -0 KB
20 legacy format
2 missing dimensions CLS risk

Set explicit width and height to prevent CLS.

Why this matters

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.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

C
JS Execution Cost
Action
1237ms total JS execution
REVIEW
1237ms total JS execution
Info::
https://www.uottawa.ca/sites/g/files/bhrskd331/fil...: 179ms CPU time
Info::
https://analytics.tiktok.com/i18n/pixel/static/mai...: 154ms CPU time
Info::
https://www.uottawa.ca/en: 150ms CPU time
Info::
Unattributable: 130ms CPU time
Info::
https://www.uottawa.ca/sites/g/files/bhrskd331/fil...: 124ms CPU time
Warning::
Third-party scripts: 784ms (63% of total)

Main Thread Breakdown

Script Evaluation 54% Other 16% Script Parsing & Compilation 13% Style & Layout 12%
ScriptTotalScriptingParse/CompileParty
https://www.uottawa.ca/sites/g/files/bhrskd331/files/js/js_RwRTj6aqZvVFwsXo8YH2VV__7Q3-Ju6FJTvoqAXpWZU.js?scope=header&delta=0&language=en&theme=uottawa&include=eJx1kGtuwzAMgy_kzLuRIbuKy0V-wFbbpKevlwFpO2x_KOiTIBLyQvfNepQP-qLV8MWFUhbwKKkKKAd2UZP9b2BiKVHYKUUbh_zuf86-wWQwN0rsGnfcuVlkqNlzfIsR-EZtc52phbN9b4d9nhHdXFoyl6JKN7KBUiXEzO1AMwX2I_BUsbI8MdbdfBwLgXuHh0C317mSRz7x-vn3RpTiSaaumyDHA3coI9VWrvxkgrBMQ08vwXqmGs6kB1AseuS8gm_d7rp_7gFk_6Nb179ms100ms8ms1st
https://analytics.tiktok.com/i18n/pixel/static/main.MWE0ZWQ3ZWQwMQ.js154ms80ms63ms3rd
https://www.uottawa.ca/en150ms2ms0ms1st
Unattributable130ms5ms0ms3rd
https://www.uottawa.ca/sites/g/files/bhrskd331/files/js/js_f6HUhyIqRKOI6LbMUIhd4AvYW3d-YV_AaD9LZR5k6yY.js?scope=footer&delta=2&language=en&theme=uottawa&include=eJx1kGtuwzAMgy_kzLuRIbuKy0V-wFbbpKevlwFpO2x_KOiTIBLyQvfNepQP-qLV8MWFUhbwKKkKKAd2UZP9b2BiKVHYKUUbh_zuf86-wWQwN0rsGnfcuVlkqNlzfIsR-EZtc52phbN9b4d9nhHdXFoyl6JKN7KBUiXEzO1AMwX2I_BUsbI8MdbdfBwLgXuHh0C317mSRz7x-vn3RpTiSaaumyDHA3coI9VWrvxkgrBMQ08vwXqmGs6kB1AseuS8gm_d7rp_7gFk_6Nb124ms38ms16ms1st
https://www.redditstatic.com/ads/pixel.js121ms97ms2ms3rd
https://www.googletagmanager.com/gtag/js?id=G-GKVJ53FL3H&cx=c&gtm=4e6460109ms96ms12ms3rd
https://www.googletagmanager.com/gtm.js?id=GTM-WVKZFC107ms91ms13ms3rd
https://www.googletagmanager.com/gtag/js?id=AW-873072808&cx=c&gtm=4e646088ms79ms9ms3rd
https://connect.facebook.net/en_US/fbevents.js74ms39ms35ms3rd
A
Third-Party Impact
22% third-party, 0 ms blocking
PASS
22% third-party, 0 ms blocking
Info::
Third-party code accounts for 22% of page weight (1.1 MiB of 5.1 MiB)
Info::
Third-party blocking time is low (0 ms)
78%
22%
First-party Third-party
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+
Font Loading
4 fonts (203 KB)
PASS
4 fonts (203 KB)
Info::
4 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

4

203 KB total

Render-blocking

0

of 4

Dominant font-display

swap

Most common across fonts

Font loading timeline
Transfer FOIT (block) FOUT (swap)
0 ms 1.0 s 2.0 s 3.0 s 4.0 s FCP 965 ms LCP 3.8 shttps://fonts.gstatic.com/s/worksans/v24/QGYsz_wNahGAdqQ43Rh_fKDptfpA4Q.woff2QGYsz_wNahGAdqQ43Rh_fKD... https://fonts.gstatic.com/s/worksans/v24/QGYsz_wNahGAdqQ43Rh_fKDptfpA4Q.woff2 — 49.4 KiB — 0 ms — font-display: swaphttps://fonts.gstatic.com/s/materialicons/v145/flUhRq6tzZclQEJ-Vdg-IuiaDsNcIhQ8tQ.woff2flUhRq6tzZclQEJ-Vdg-Iui... https://fonts.gstatic.com/s/materialicons/v145/flUhRq6tzZclQEJ-Vdg-IuiaDsNcIhQ8tQ.woff2 — 125.6 KiB — 0 ms — font-display: swaphttps://fonts.gstatic.com/s/spectral/v15/rnCr-xNNww_2s0amA9M5knjsS_ul.woff2rnCr-xNNww_2s0amA9M5knj... https://fonts.gstatic.com/s/spectral/v15/rnCr-xNNww_2s0amA9M5knjsS_ul.woff2 — 13.7 KiB — 0 ms — font-display: swaphttps://fonts.gstatic.com/s/spectral/v15/rnCs-xNNww_2s0amA9uSsG3BafaPWnII.woff2rnCs-xNNww_2s0amA9uSsG3... https://fonts.gstatic.com/s/spectral/v15/rnCs-xNNww_2s0amA9uSsG3BafaPWnII.woff2 — 14.5 KiB — 0 ms — font-display: swap
QGYsz_wNahGAdqQ43Rh_fKD... woff2 swap
Size 49 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
flUhRq6tzZclQEJ-Vdg-Iui... woff2 swap
Size 126 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
  • Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
rnCr-xNNww_2s0amA9M5knj... woff2 swap
Size 14 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
rnCs-xNNww_2s0amA9uSsG3... woff2 swap
Size 15 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
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 ~63 KB and ~126 ms

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+
Green Hosting
Whether the site is served from green-energy infrastructure
PASS

Green Hosting

This site is hosted on green energy infrastructure

Provider: Cloudflare

A
HTTP Caching
max-age=900 (15 minutes)
PASS
max-age=900 (15 minutes)
Info::
Cache-Control header is set
Got: max-age=900, public
Info::
Effective TTL: 15 minutes (max-age=900)
Info::
No ETag or Last-Modified header
Conditional requests (304 Not Modified) are not possible without validators.
Cache-Control

max-age=900, public

DirectiveValueMeaning
max-age900Cache for 15 minutes
public—Any cache may store this response
Effective TTL: 900 seconds
Network Waterfall
99 requests over 0ms
INFO

Performance analysis not available for this result.

Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
63% of JavaScript execution is third-party
First-party Third-party 784ms · 712KB · CA$11/mo
analytics.tiktok.com
Other
Optional
Execution 154ms
Transfer 110 KB
Unused 51%
Monthly Cost CA$2/mo
Unattributable
Other
Optional
Execution 130ms
Transfer 0 KB
Monthly Cost CA$2/mo
www.redditstatic.com
Other
Optional
Execution 121ms
Transfer 19 KB
Monthly Cost CA$2/mo
Google Tag Manager
Tag Manager
Optional
Execution 109ms
Transfer 178 KB
Unused 36%
Monthly Cost CA$2/mo
Google Tag Manager
Tag Manager
Optional
Execution 107ms
Transfer 165 KB
Unused 38%
Monthly Cost CA$1/mo
Google Tag Manager
Tag Manager
Optional
Execution 88ms
Transfer 146 KB
Unused 42%
Monthly Cost CA$1/mo
Facebook Pixel
Advertising
Optional
Execution 74ms
Transfer 95 KB
Unused 34%
Monthly Cost CA$1/mo

63% 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

51% of analytics.tiktok.com'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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