Performance
· 15 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.
888 ms
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
1.22 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
0 ms
Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.
0.443
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
1.00 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.
1.22 s
Page Load Progression
DThird-Party ImpactAction86% third-party, 0 ms blockingFIX
CImage OptimizationAction30 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
BJS Execution Cost507ms total JS executionREVIEW
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://slashdot.org/ | 237ms | 26ms | 4ms | 1st |
| Unattributable | 79ms | 2ms | 0ms | 3rd |
| https://slashdot.org/cdn-cgi/challenge-platform/scripts/jsd/main.js | 68ms | 63ms | 1ms | 1st |
| https://a.fsdn.com/sd/all-minified.js?a6bec9f7b7c53257 | 68ms | 32ms | 9ms | 3rd |
| https://cdn.consentmanager.net/delivery/customdata/bV8xLndfMTIxMjYucl9HRFBSLmxfZW4uZF8yNDkyLnhfMTUudi5wLnRfMjQ5Mi54dF84Mg.js | 55ms | 49ms | 1ms | 3rd |
BJS Bundles13 scripts, 128 KB unusedREVIEW
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://a.fsdn.com/sd/all-minified.js?a6bec9f7b7c53257 | 128 KB | 92 KB (72%) | ✓ | 3rd |
| https://cdn.consentmanager.net/delivery/js/cmp_en.min.js | 100 KB | 36 KB (36%) | ✓ | 3rd |
| https://d.delivery.consentmanager.net/delivery/cmp.php?&cdid=dba15d148b97&h=https%3A%2F%2Fslashdot.org%2F&cmpregulationkey=GDPR&&l=en&o=1776295472522 | 1 KB | — | ✓ | 3rd |
| https://a.fsdn.com/sd/js/scripts/asg_embed.js?a6bec9f7b7c53257 | 0 KB | — | ✓ | 3rd |
| https://a.fsdn.com/con/js/sandiego/maxnav.js?2026-04-09 | 1 KB | — | ✓ | 3rd |
| https://a.fsdn.com/con/js/sandiego/floating-unit.js?2026-04-09 | 10 KB | — | ✗ | 3rd |
| https://a.fsdn.com/con/js/sftheme/cmp-slashdot.js?2026-04-09 | 22 KB | — | ✗ | 3rd |
| https://a.fsdn.com/sd/js/scripts/ad_top.js?a6bec9f7b7c53257 | 0 KB | — | ✓ | 3rd |
| https://analytics.slashdotmedia.com/sd.js | 23 KB | — | ✓ | 3rd |
| https://slashdot.org/cdn-cgi/challenge-platform/h/g/scripts/jsd/b0a7532ac8ec/main.js? | 12 KB | — | ✓ | 1st |
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
BHTTP Cachingno-cacheREVIEW
no-cache
| Directive | Value | Meaning |
|---|---|---|
| no-cache | — | Cache but always revalidate first |
APage Weight Budget716 KB transferred, 62 requestsPASS
A+Text CompressionAll text resources are compressedPASS
A+Font Loading3 fonts (92 KB)PASS
Web fonts
3
92 KB total
Render-blocking
0
of 3
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 ~13 KB and ~26 ms
A+Resource CachingAll resources properly cachedPASS
A+Critical Rendering PathNo render-blocking resourcesPASS
A+Resource HintsNo optimization neededPASS
APage Weight Inventory62 resources · 716 KB · 128 KB savings availablePASS
~128.0 KiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 62 resources | 716.0 KiB | ||||||
A+Green HostingWhether the site is served from green-energy infrastructurePASS
Green Hosting
This site is hosted on green energy infrastructure
Provider: Cloudflare
Network Waterfall62 requests over 1404msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
Unattributable Unattributable | Other | 79ms | 0 KB | — | €1/mo | Optional |
a.fsdn.com a.fsdn.com | Other | 68ms | 128 KB | 72% | €1/mo | Optional |
cdn.consentmanager.net cdn.consentmanager.net | Other | 55ms | 16 KB | — | €1/mo | Optional |
72% of a.fsdn.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