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Lighthouse lab metrics, Axe, and Chrome UX Report field data for a list of sites recorded and compared over time. Follow us on Mastodon or Bluesky.

Charts Compare Measurement runs Embed a score Open to Work

simplyexplained.com

https://simplyexplained.com/

90PERF 93A11Y 100BEST 92SEO AXE CWV

Ranks Overall #1,152 Built Awesome #888

Data from Sep 20, 2026, 6:07 PM UTC old Measured once a week · 6 runs since Aug 21, 2026

Elsewhere: PageSpeed Insights · Calibre · Treo · CrUX Vis · Tame the Bots · Scoring Calculator · Wayback Machine

Moved from https://savjee.be/.

History from the previous URL is included below, with the move on Sep 6, 2026. A step-change around that point is likely the change of address rather than a regression.

Lab data is measured using Lighthouse, Mobile mode unless otherwise specified. Field data is reported from Chrome UX Report (using p75 measurements).

Stack

Eleventy 2.0.1 Built with Eleventy 2.0.1
Cloudflare Hosted by Cloudflare

Lighthouse Scores LAB Simulated

90
Performance
no change
93
Accessibility
no change
100
Best Practices
no change
92
SEO
no change

Metrics LAB FIELD

Core Web Vitals: passing 3 of 3 assessed from real Chrome users.

Field figures are the p75 across real Chrome users over a 28-day trailing window (2026-08-22 → 2026-09-18), origin-level.

Metric Lab Simulated Field
Value Change / range Trend p75 Distribution
LCP CWV Largest Contentful Paint 3.23 s needs work ↑ +181 ms (+5.9%) 3.04 s – 4.06 s 1.18 s good 96.6% 3% 0.5%
INP CWV Interaction to Next Paint — field only, no lab run can measure it n/a 57 ms good 100% 0% 0%
CLS CWV Cumulative Layout Shift 0.100 good → no change 0 – 0.100 0 good 95.4% 2.5% 2.1%
TBT Total Blocking Time 0 ms good ↓ -169 ms (-100%) significant 0 ms – 169 ms n/a
FCP First Contentful Paint 1.25 s good ↑ +413 ms (+49.3%) 837 ms – 2.06 s 1.09 s good 95.2% 2.5% 2.4%
Speed Index 1.25 s good ↑ +413 ms (+49.3%) 837 ms – 2.06 s n/a
TTFB Time to First Byte 475 ms good ↓ -169 ms (-26.2%) 475 ms – 644 ms 545 ms good 86.3% 13.2% 0.5%

LCP Subparts LAB Unthrottled

The subparts attribute LCP to your server, resource discovery, download, or rendering. Note that the Lab LCP shown above is a simulated throttled estimate.

element render delay 120 ms
resource load delay 55 ms
resource load duration 38 ms
time to first byte 14 ms

LCP LAB Simulated vs LCP FIELD

Lab 3.23 s
Field p75 1.18 s

The lab LCP is 2.74× the field p75 — real users likely have above-average hardware or network connectivity.

Page weight

Metric Value Change / range Trend
Page Weight 459 kB ↑ +4.3 kB (+1%) 455 kB – 474 kB
Requests 12 → no change 12 – 13
Third-party Weight 20.3 kB ↓ -349 B (-1.7%) 20.3 kB – 473 kB
Third-party CPU 0 ms → no change 0 ms – 5 ms
Unused JS 0 B → no change 0 B – 0 B
Unused CSS 0 B → no change 0 B – 0 B

By resource type

Type Transfer Share Size Requests
image 97.5% 443 kB 6
document 1.7% 7.9 kB 1
stylesheet 0.3% 1.5 kB 1
script 0.3% 1.5 kB 1
other 0.1% 604 B 1
Total 459 kB 12

Third parties 1 entities

Entity Transfer Size Main thread Simulated
YouTube image 20.3 kB 0 ms
Total 20.3 kB 0 ms

Page health

Metric Value Change / range Trend
Main Thread Work 225 ms ↓ -224 ms (-49.9%) 205 ms – 1.10 s
Long Tasks 0 ↓ -1 (-100%) 0 – 2
DOM Elements 128 → no change 128 – 128
Axe Violations Violating nodes from a full Axe CLI run (more than Lighthouse reports) 21 → no change 21 – 25
A11y Failures 2 → no change 2 – 2
A11y Failing Nodes 17 → no change 17 – 17

Main thread work

Task Time Share Duration Simulated
other 51% 114 ms
style layout 26% 60 ms
script evaluation 8% 18 ms
parse HTML 7% 16 ms
paint composite render 7% 15 ms
script parse compile 1% 2 ms
Total 225 ms

Axe violations axe-core 4.13.0, full rule set

21 violating nodes across 4 rules, 217 passing. This is a standalone Axe CLI run and is stricter than the subset Lighthouse already includes.

  • serious color-contrast — Elements must meet minimum color contrast ratio thresholds 16 nodes
  • moderate region — All page content should be contained by landmarks 3 nodes
  • moderate landmark-one-main — Document should have one main landmark 1 node
  • moderate page-has-heading-one — Page should contain a level-one heading 1 node

Accessibility failures 2 of 18 audits

  • color-contrast — Background and foreground colors do not have a sufficient contrast ratio. 16 nodes
  • landmark-one-main — Document does not have a main landmark. 1 node

SEO failures 1 of 10 audits

  • link-text — Links do not have descriptive text 1 item

Hygiene

HTTPS HSTS CSP Clickjacking protection Origin isolation Trusted Types bfcache h3

Measurement log

Every stored run for this URL, newest first.

When Scores PerfLCPCLSTBTWeight RunsSpreadBenchTook Archive
Sep 20, 2026, 6:07 PM UTC 90 3.23 s 0.100 0 ms 459 kB 3/3 ±4 2,488 0% 21.2s Wayback
Sep 13, 2026, 5:26 PM UTC 90 3.04 s 0.100 169 ms 455 kB 3/3 ±7 2,519 +1% 20.9s Wayback
Sep 6, 2026, 4:45 PM UTC 92 3.32 s 0 0 ms 460 kB 3/3 ±8 2,993 +20% 23.3s Wayback
Sep 6, 2026, 10:25 AM UTC old URL 84 4.06 s 0.100 0 ms 460 kB 3/3 ±3 2,346 -6% 20.8s Wayback
Aug 30, 2026, 8:00 AM UTC old URL 89 3.65 s 0 0 ms 459 kB 3/3 ±5 2,764 +11% 21.5s Wayback
Aug 21, 2026, 3:36 PM UTC old URL 86 3.98 s 0 0 ms 474 kB 3/3 ±4 2,370 -5% 23s Wayback

Embed this score

Use this web component to show simplyexplained.com's scores on any website, updated whenever this instance re-measures. Don’t forget to bundle the speedlify2-score.js component code into your site!

<speedlify2-score speedlify-url="https://www.speedlify.dev/" url="https://simplyexplained.com/"></speedlify2-score>