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.
4.36 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
21.93 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
779 ms
Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.
0.055
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
7.16 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.
22.02 s
Page Load Progression
FPage Weight BudgetAction4.8 MB transferred, 50 requestsFIX
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
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
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.
JavaScript bundle is large — code-split routes and lazy-load off-screen components to defer.
Source: web.dev
DThird-Party ImpactAction100% third-party, 0 ms blockingFIX
DJS Execution CostAction3109ms total JS executionFIX
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://www.lu.se/ | 895ms | 19ms | 2ms | 3rd |
| Unattributable | 637ms | 16ms | 0ms | 3rd |
| https://webstats.sgit.se/lu/matomo/matomo.js | 586ms | 562ms | 17ms | 3rd |
| https://www.lu.se/sites/www.lu.se/files/js/js_XmiqJKuiyACXkn6McDpuKnkst_1k14KJeCJCsF_GdQg.js?scope=header&delta=0&language=sv&theme=lu_theme&include=eJxtju0KwzAIRV-okEcKJrFdNvWGfFD29gvbj3RQUK6cgygPH4FX5hlaJJNFdnwDNxm-P1jZBYov3zGrXCDQW69UvCfh2m9NhAiVxrdSkUiWSRUl4bQLeRtpjl7ZhhdQ4rrkIQjX9WfzJ1XLdiw2h1BxNp4vYqQ_saPqAkrZvnc2pQ6F-8XWCulscwj7aJE6fwCe3X6W | 444ms | 181ms | 17ms | 3rd |
| https://www.browsealoud.com/modules/3.11.0/6514.ac3cda7a458b82b8b52f.js | 176ms | 124ms | 48ms | 3rd |
| https://www.browsealoud.com/modules/3.11.0/740.c7c59a28c7aa37bb0e0b.js | 119ms | 109ms | 2ms | 3rd |
| https://www.lu.se/sites/www.lu.se/files/js/js_5e9TuwewO-yJ98xVtloTwewBKJvyXCqsz_VFDQ6ICt8.js?scope=footer&delta=0&language=sv&theme=lu_theme&include=eJxtju0KwzAIRV-okEcKJrFdNvWGfFD29gvbj3RQUK6cgygPH4FX5hlaJJNFdnwDNxm-P1jZBYov3zGrXCDQW69UvCfh2m9NhAiVxrdSkUiWSRUl4bQLeRtpjl7ZhhdQ4rrkIQjX9WfzJ1XLdiw2h1BxNp4vYqQ_saPqAkrZvnc2pQ6F-8XWCulscwj7aJE6fwCe3X6W | 114ms | 81ms | 28ms | 3rd |
| https://www.lu.se/sites/www.lu.se/files/css/css_7WNU9q669fKX4vcClKUzoQP9iPUZZblmu1hsL4jYhNY.css?delta=0&language=sv&theme=lu_theme&include=eJyFkwFuwyAMRS-UNkdCBtyE1WBkm3Xd6UfbaaWo0qRI8X82tvxDAoHqdfWguIRHnFEVNtQlsOAapVWgI3zA1wMUlgyUvnHBYsmuDrPHuAaolrgs2FxgPifsr1wpQQm4voPOg-By4mJwQeWM6xAfL-hvUv8tOOqe8kLN2Y69xG3EHugJPISzM-5PHSDH66jY1ASqc0Ao9jaTSm122IRbfZvPHF_GCl8Uxf2aOSSaWbfpTweQePDE4fxkUbhGvgxVpz4IZda9e2kjlOyQeljMEXikKacIEvYBNqKpx44Qx0EP7aqkDDJ4lsK4RE9uOG9xh56_BlJOPIFu6lNSKsP5Hjxc7F-FW3xJ3NZ5AQQlprK5-mJ2hlSmBTPGBKMs_XBzglq5aPrEqb42T0l3pwY2dBbVp1AMt7vv3Oye7iwWmk09jZn67V_0qob5_vP9AFI7YtU | 88ms | 0ms | 0ms | 3rd |
| https://www.lu.se/sites/www.lu.se/files/css/css_z-1nfUCG4xEKl9AZTOluEEYQ6XpsXzEp8BMGMgE5iSU.css?delta=1&language=sv&theme=lu_theme&include=eJyFkwFuwyAMRS-UNkdCBtyE1WBkm3Xd6UfbaaWo0qRI8X82tvxDAoHqdfWguIRHnFEVNtQlsOAapVWgI3zA1wMUlgyUvnHBYsmuDrPHuAaolrgs2FxgPifsr1wpQQm4voPOg-By4mJwQeWM6xAfL-hvUv8tOOqe8kLN2Y69xG3EHugJPISzM-5PHSDH66jY1ASqc0Ao9jaTSm122IRbfZvPHF_GCl8Uxf2aOSSaWbfpTweQePDE4fxkUbhGvgxVpz4IZda9e2kjlOyQeljMEXikKacIEvYBNqKpx44Qx0EP7aqkDDJ4lsK4RE9uOG9xh56_BlJOPIFu6lNSKsP5Hjxc7F-FW3xJ3NZ5AQQlprK5-mJ2hlSmBTPGBKMs_XBzglq5aPrEqb42T0l3pwY2dBbVp1AMt7vv3Oye7iwWmk09jZn67V_0qob5_vP9AFI7YtU | 50ms | 0ms | 0ms | 3rd |
DPage Weight InventoryAction50 resources · 4.8 MB · 225 KB savings availableFIX
~224.8 KiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 50 resources | 4.8 MiB | ||||||
FHTTP CachingActionNo cache headersFIX
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
CImage OptimizationAction19 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
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
CJS BundlesAction17 scripts, 225 KB unusedREVIEW
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://webstats.sgit.se/lu/matomo/matomo.js | 133 KB | 75 KB (57%) | ✓ | 3rd |
| https://www.browsealoud.com/modules/3.11.0/4230.c222ded98d9c6a4219ab.js | 82 KB | 70 KB (85%) | ✓ | 3rd |
| https://www.browsealoud.com/modules/3.11.0/6514.ac3cda7a458b82b8b52f.js | 104 KB | 40 KB (39%) | ✓ | 3rd |
| https://www.lu.se/sites/www.lu.se/files/js/js_5e9TuwewO-yJ98xVtloTwewBKJvyXCqsz_VFDQ6ICt8.js?scope=footer&delta=0&language=sv&theme=lu_theme&include=eJxtju0KwzAIRV-okEcKJrFdNvWGfFD29gvbj3RQUK6cgygPH4FX5hlaJJNFdnwDNxm-P1jZBYov3zGrXCDQW69UvCfh2m9NhAiVxrdSkUiWSRUl4bQLeRtpjl7ZhhdQ4rrkIQjX9WfzJ1XLdiw2h1BxNp4vYqQ_saPqAkrZvnc2pQ6F-8XWCulscwj7aJE6fwCe3X6W | 54 KB | 39 KB (73%) | ✓ | 3rd |
| https://www.browsealoud.com/modules/3.11.0/4916.dd13ed0cd26117b33f9d.js | 30 KB | — | ✓ | 3rd |
| https://plus.browsealoud.com/js/urlinfo/www.lu.se.js | 1 KB | — | ✓ | 3rd |
| https://www.browsealoud.com/modules/3.11.0/browsealoud.js | 41 KB | — | ✓ | 3rd |
| https://plus.browsealoud.com/js/urlinfo/www.lu.se.js | 0 KB | — | ✓ | 3rd |
| https://www.lu.se/sites/www.lu.se/files/js/js_XmiqJKuiyACXkn6McDpuKnkst_1k14KJeCJCsF_GdQg.js?scope=header&delta=0&language=sv&theme=lu_theme&include=eJxtju0KwzAIRV-okEcKJrFdNvWGfFD29gvbj3RQUK6cgygPH4FX5hlaJJNFdnwDNxm-P1jZBYov3zGrXCDQW69UvCfh2m9NhAiVxrdSkUiWSRUl4bQLeRtpjl7ZhhdQ4rrkIQjX9WfzJ1XLdiw2h1BxNp4vYqQ_saPqAkrZvnc2pQ6F-8XWCulscwj7aJE6fwCe3X6W | 38 KB | — | ✓ | 3rd |
| https://www.browsealoud.com/modules/3.11.0/2191.b9fbc2ad4e19a0ccda54.js | 10 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
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 Loading7 fonts (2617 KB)PASS
Web fonts
7
2617 KB total
Render-blocking
0
of 7
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
- 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
- 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 ~1309 KB and ~2618 ms
A+Resource CachingAll resources properly cachedPASS
A+Critical Rendering PathNo render-blocking resourcesPASS
A+Resource Hints5 hints, 0 missing preconnectsPASS
Current Resource Hints
5 resource hints configured
A+Render-Blocking ResourcesNo render-blocking resources detectedPASS
A+Third-Party ResourcesNo third-party resources detectedPASS
Network Waterfall50 requests over 4023msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
www.lu.se www.lu.se | Other | 895ms | 20 KB | — | kr97/mo | Costly |
Unattributable Unattributable | Other | 637ms | 0 KB | — | kr69/mo | Costly |
webstats.sgit.se webstats.sgit.se | Other | 586ms | 133 KB | 57% | kr64/mo | Costly |
www.lu.se www.lu.se | Other | 444ms | 38 KB | — | kr48/mo | Costly |
www.browsealoud.com www.browsealoud.com | Other | 176ms | 104 KB | 39% | kr19/mo | Optional |
www.browsealoud.com www.browsealoud.com | Other | 119ms | 4 KB | — | kr13/mo | Optional |
www.lu.se www.lu.se | Other | 114ms | 54 KB | 73% | kr12/mo | Optional |
www.lu.se www.lu.se | Other | 88ms | 100 KB | — | kr10/mo | Optional |
www.lu.se www.lu.se | Other | 50ms | 48 KB | — | kr5/mo | Optional |
These scripts may cost more than they're worth
- www.lu.se adds 895ms and costs ~kr97/month
- Unattributable adds 637ms and costs ~kr69/month
- webstats.sgit.se adds 586ms and costs ~kr64/month
- www.lu.se adds 444ms and costs ~kr48/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.lu.se takes 895ms 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 637ms 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
webstats.sgit.se takes 586ms 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
57% of webstats.sgit.se'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.lu.se takes 444ms 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
73% of www.lu.se'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