tc39.es

Ranks Overall #542 Built Awesome #408

Data from Oct 4, 2026, 10:48 PM UTC 3d old Measured once a week · 7 runs since Aug 21, 2026

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

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

Stack

Hosted by GitHub Pages

Lighthouse Scores LAB Simulated

Performance

↑ +6 (+6.7%)

100

Accessibility

no change

100

Best Practices

no change

SEO

no change

Metrics LAB FIELD

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

Field figures are the p75 across real Chrome users over a 28-day trailing window (2026-09-05 → 2026-10-02), origin-level.

Metric	Lab Simulated	Field
LCP CWV Largest Contentful Paint	1.53 s good	↓ -909 ms (-37.2%) significant 1.53 s – 2.60 s	1.48 s good	89.7% 5.4% 4.9%
INP CWV Interaction to Next Paint — field only, no lab run can measure it	n/a	—	335 ms needs work	62.2% 19.3% 18.5%
CLS CWV Cumulative Layout Shift	0.120 needs work	→ no change 0.120 – 0.330	0 good	88.7% 3% 8.3%
TBT Total Blocking Time	0 ms good	→ no change 0 ms – 0 ms	n/a	—
FCP First Contentful Paint	1.53 s good	↓ -909 ms (-37.2%) significant 1.53 s – 2.60 s	1.63 s good	77.8% 10.2% 12.1%
Speed Index	1.53 s good	↓ -909 ms (-37.2%) significant 1.53 s – 2.60 s	n/a	—
TTFB Time to First Byte	610 ms good	↑ +8 ms (+1.3%) 602 ms – 610 ms	533 ms good	85% 11.9% 3.2%

Metric

Lab Simulated

Field

Value

Change / range

Trend

p75

Distribution

LCP CWV Largest Contentful Paint

1.53 s good

↓ -909 ms (-37.2%) significant 1.53 s – 2.60 s

1.48 s good

89.7% 5.4% 4.9%

INP CWV Interaction to Next Paint — field only, no lab run can measure it

n/a

—

335 ms needs work

62.2% 19.3% 18.5%

CLS CWV Cumulative Layout Shift

0.120 needs work

→ no change 0.120 – 0.330

0 good

88.7% 3% 8.3%

TBT Total Blocking Time

0 ms good

→ no change 0 ms – 0 ms

n/a

—

FCP First Contentful Paint

1.53 s good

↓ -909 ms (-37.2%) significant 1.53 s – 2.60 s

1.63 s good

77.8% 10.2% 12.1%

Speed Index

1.53 s good

↓ -909 ms (-37.2%) significant 1.53 s – 2.60 s

n/a

—

TTFB Time to First Byte

610 ms good

↑ +8 ms (+1.3%) 602 ms – 610 ms

533 ms good

85% 11.9% 3.2%

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 62 ms

time to first byte 11 ms

LCP LAB Simulated vs LCP FIELD

Lab 1.53 s

Field p75 1.48 s

The lab LCP is 1.04× the field p75 — real users likely have similar hardware or network connectivity to the lab test.

Page weight

Metric	Value	Change / range
Page Weight	73.7 kB	↓ -112 B (-0.2%) 73.7 kB – 99.7 kB
Requests	9	→ no change 9 – 12
Third-party Weight	45.2 kB	→ no change 45.2 kB – 68.0 kB
Third-party CPU	0 ms	→ no change 0 ms – 0 ms
Unused JS	0 B	→ no change 0 B – 0 B
Unused CSS	0 B	→ no change 0 B – 0 B

Metric

Value

Change / range

Trend

Page Weight

73.7 kB

↓ -112 B (-0.2%) 73.7 kB – 99.7 kB

Requests

→ no change 9 – 12

Third-party Weight

45.2 kB

→ no change 45.2 kB – 68.0 kB

Third-party CPU

0 ms

→ no change 0 ms – 0 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	Share	Size	Requests
font	59.5%	43.0 kB	1
image	20.9%	15.1 kB	2
document	9.3%	6.7 kB	1
stylesheet	9.2%	6.7 kB	3
script	1.1%	765 B	1
Total		73.7 kB	9

Third parties 1 entities

Entity	Transfer	Size	Main thread Simulated
Google Fonts	font	45.2 kB	0 ms
Total		45.2 kB	0 ms

Entity

Transfer

Size

Main thread Simulated

Google Fonts

font

45.2 kB

0 ms

Total

45.2 kB

0 ms

Page health

Metric	Value	Change / range
Main Thread Work	208 ms	↓ -23 ms (-9.9%) 208 ms – 342 ms
Long Tasks	0	→ no change 0 – 0
DOM Elements	306	↓ -20 (-6.1%) significant 306 – 357
Axe Violations Violating nodes from a full Axe CLI run (more than Lighthouse reports)	0	→ no change 0 – 1
A11y Failures	0	→ no change 0 – 1
A11y Failing Nodes	0	→ no change 0 – 1

Metric

Value

Change / range

Trend

Main Thread Work

208 ms

↓ -23 ms (-9.9%) 208 ms – 342 ms

Long Tasks

→ no change 0 – 0

DOM Elements

306

↓ -20 (-6.1%) significant 306 – 357

Axe Violations Violating nodes from a full Axe CLI run (more than Lighthouse reports)

→ no change 0 – 1

A11y Failures

→ no change 0 – 1

A11y Failing Nodes

→ no change 0 – 1

Main thread work

Task	Share	Duration Simulated
other	43%	89 ms
style layout	35%	74 ms
paint composite render	9%	19 ms
script evaluation	6%	13 ms
parse HTML	6%	13 ms
script parse compile	1%	1 ms
Total		208 ms

Task

Time

Duration Simulated

other

43%

89 ms

style layout

35%

74 ms

paint composite render

19 ms

script evaluation

13 ms

parse HTML

13 ms

script parse compile

1 ms

Total

208 ms

Axe violations axe-core 4.13.0, full rule set

0 violating nodes across 0 rules, 618 passing. This is a standalone Axe CLI run and is stricter than the subset Lighthouse already includes.

SEO failures 1 of 8 audits

meta-description — Document does not have a meta description

Hygiene

HTTPS HSTS CSP Clickjacking protection Origin isolation Trusted Types bfcache h2

Measurement log

Field history 25 weeks

Weekly p75 from the CrUX History API, backfilled in a single request.

Week ending	LCP	INP	FCP	TTFB
2026-09-26	1.63 s	376 ms	1.85 s	606 ms
2026-09-19	1.72 s	392 ms	1.95 s	605 ms
2026-09-12	1.74 s	382 ms	1.91 s	589 ms
2026-09-05	1.77 s	413 ms	2.01 s	592 ms
2026-08-29	1.85 s	456 ms	2.06 s	563 ms
2026-08-22	1.53 s	454 ms	1.53 s	578 ms
2026-08-15	1.53 s	481 ms	1.53 s	593 ms
2026-08-08	1.87 s	449 ms	1.69 s	556 ms
2026-08-01	1.70 s	402 ms	1.71 s	850 ms
2026-07-25	1.57 s	447 ms	1.57 s	599 ms
2026-07-18	1.56 s	429 ms	1.56 s	602 ms
2026-07-11	1.33 s	401 ms	1.30 s	773 ms

Week ending

LCP

INP

CLS

FCP

TTFB

2026-09-26

1.63 s

376 ms

1.85 s

606 ms

2026-09-19

1.72 s

392 ms

1.95 s

605 ms

2026-09-12

1.74 s

382 ms

1.91 s

589 ms

2026-09-05

1.77 s

413 ms

2.01 s

592 ms

2026-08-29

1.85 s

456 ms

2.06 s

563 ms

2026-08-22

1.53 s

454 ms

1.53 s

578 ms

2026-08-15

1.53 s

481 ms

1.53 s

593 ms

2026-08-08

1.87 s

449 ms

1.69 s

556 ms

2026-08-01

1.70 s

402 ms

1.71 s

850 ms

2026-07-25

1.57 s

447 ms

1.57 s

599 ms

2026-07-18

1.56 s

429 ms

1.56 s

602 ms

2026-07-11

1.33 s

401 ms

1.30 s

773 ms

Runs

Every stored run for this URL, newest first.

When	Perf	LCP	CLS	Weight	Runs	Spread	Bench	Took	Archive
Oct 4, 2026, 10:48 PM UTC	96	1.53 s	0.120	73.7 kB	3/3	±3	2,667 +7%	22.1s	Wayback
Sep 27, 2026, 8:58 PM UTC	90	2.44 s	0.120	73.8 kB	3/3	±1	2,485 0%	22.2s	Wayback
Sep 20, 2026, 2:37 PM UTC	78	2.46 s	0.330	99.6 kB	3/3	±1	3,400 +37%	20.6s	Wayback
Sep 13, 2026, 1:51 PM UTC	77	2.60 s	0.330	99.5 kB	3/3	±2	2,343 -6%	21.1s	Wayback
Sep 6, 2026, 10:27 AM UTC	78	2.45 s	0.330	99.5 kB	3/3	±4	2,480 0%	22.3s	Wayback
Aug 30, 2026, 8:01 AM UTC	77	2.58 s	0.330	99.7 kB	3/3	±1	2,446 -2%	21.2s	Wayback
Aug 21, 2026, 8:44 AM UTC	78	2.46 s	0.330	99.6 kB	3/3	±13	3,332 +34%	21.6s	Wayback

When

Scores

Perf

LCP

CLS

TBT

Weight

Runs

Spread

Bench

Took

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Stack

Lighthouse Scores LAB 🤖 Simulated

Metrics LAB FIELD

LCP Subparts LAB 🐇 Unthrottled

LCP LAB 🤖 Simulated vs LCP FIELD

Page weight

By resource type

Third parties 1 entities

Page health

Main thread work

Axe violations axe-core 4.13.0, full rule set

SEO failures 1 of 8 audits

Hygiene

Measurement log

Field history 25 weeks

Runs

Embed this score

Lighthouse Scores LAB Simulated

LCP Subparts LAB Unthrottled

LCP LAB Simulated vs LCP FIELD