pkg.go.dev

https://pkg.go.dev/

Data from Aug 25, 2026, 4:36 PM UTC 13h old

Overall #1,188 Package Managers #6 · 1 measurement · since Aug 25, 2026

Stack

Detected on the same page load as the accessibility pass — the generator from <meta name="generator"> or the shape of the page, the host from response headers.

Go Hosted by Google Frontend

Core Web Vitals field data, url-level

Real Chrome users, 28-day window (2026-07-27 → 2026-08-23). This is what Google measures you on.

LCP 1.34 s good

INP 118 ms good

CLS 0 good

Scores

Performance

no change

Accessibility

no change

100

Best Practices

no change

SEO

no change

Filmstrip Lighthouse, mobile

How the page drew during the measured load, at 8 points across 3.00 s.

375 ms
750 ms
1.13 s
1.50 s
1.88 s
2.25 s
2.63 s
3.00 s

Lab metrics Lighthouse, mobile

Metric	Current	Previous	Change	Best	Worst
LCP Largest Contentful Paint	2.88 s	—	—	2.88 s	2.88 s
CLS Cumulative Layout Shift	0.011	—	—	0.011	0.011
TBT Total Blocking Time	147 ms	—	—	147 ms	147 ms
FCP First Contentful Paint	1.28 s	—	—	1.28 s	1.28 s
Speed Index	1.35 s	—	—	1.35 s	1.35 s
TTFB Time to First Byte	682 ms	—	—	682 ms	682 ms

What LCP is made of observed, unthrottled

A flat LCP number tells you something regressed. The subparts tell you whether it was the server, resource discovery, the download, or rendering.

Measured on the trace before throttling is modelled, so these are real durations that will not sum to the 2.88 s above — that figure is a simulation of the same load on a slow phone and connection. Read these for the proportions: which phase dominates.

resource load duration 173 ms

time to first byte 80 ms

element render delay 26 ms

resource load delay 12 ms

Field data Chrome UX Report, url-level

Real Chrome users, 28-day trailing window (2026-07-27 → 2026-08-23). This is what Google measures you on.

Metric	p75	Rating	Distribution (good / needs work / poor)
LCP CWV	1.34 s	good	93.1% good
INP CWV Interaction to Next Paint — field only, Lighthouse cannot measure this in a lab run	118 ms	good	88% good
CLS CWV	0	good	99.7% good
FCP	1.17 s	good	90.8% good
TTFB	628 ms	good	85.9% good

Metric

p75

Rating

Distribution (good / needs work / poor)

LCP CWV

1.34 s

good

93.1% good

INP CWV Interaction to Next Paint — field only, Lighthouse cannot measure this in a lab run

118 ms

good

88% good

CLS CWV

good

99.7% good

FCP

1.17 s

good

90.8% good

TTFB

628 ms

good

85.9% good

Lab vs field

Lab LCP 2.88 s · field p75 1.34 s · real users are 0.46× faster than the lab.

Field history 25 weeks

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

Week ending	LCP	INP	FCP	TTFB
2026-08-22	1.34 s	118 ms	1.17 s	627 ms
2026-08-15	1.32 s	116 ms	1.19 s	597 ms
2026-08-08	1.34 s	108 ms	1.20 s	605 ms
2026-08-01	1.29 s	106 ms	1.16 s	586 ms
2026-07-25	1.24 s	106 ms	1.14 s	558 ms
2026-07-18	1.23 s	105 ms	1.10 s	565 ms
2026-07-11	1.23 s	106 ms	1.10 s	579 ms
2026-07-04	1.25 s	111 ms	1.13 s	587 ms
2026-06-27	1.21 s	111 ms	1.11 s	586 ms
2026-06-20	1.23 s	116 ms	1.13 s	607 ms
2026-06-13	1.23 s	120 ms	1.13 s	589 ms
2026-06-06	1.25 s	120 ms	1.10 s	611 ms

Week ending

LCP

INP

CLS

FCP

TTFB

2026-08-22

1.34 s

118 ms

1.17 s

627 ms

2026-08-15

1.32 s

116 ms

1.19 s

597 ms

2026-08-08

1.34 s

108 ms

1.20 s

605 ms

2026-08-01

1.29 s

106 ms

1.16 s

586 ms

2026-07-25

1.24 s

106 ms

1.14 s

558 ms

2026-07-18

1.23 s

105 ms

1.10 s

565 ms

2026-07-11

1.23 s

106 ms

1.10 s

579 ms

2026-07-04

1.25 s

111 ms

1.13 s

587 ms

2026-06-27

1.21 s

111 ms

1.11 s

586 ms

2026-06-20

1.23 s

116 ms

1.13 s

607 ms

2026-06-13

1.23 s

120 ms

1.13 s

589 ms

2026-06-06

1.25 s

120 ms

1.10 s

611 ms

Page weight

Metric	Current	Previous	Change	Best	Worst
Page Weight	545 kB	—	—	545 kB	545 kB
Requests	34	—	—	34	34
Third-party Weight	343 kB	—	—	343 kB	343 kB
Third-party CPU	78 ms	—	—	78 ms	78 ms
Unused JS	162 kB	—	—	162 kB	162 kB
Unused CSS	21.7 kB	—	—	21.7 kB	21.7 kB

By resource type

script 392 kB · 5 req

image 76.7 kB · 24 req

stylesheet 36.4 kB · 2 req

document 34.2 kB · 1 req

other 21 B · 1 req

third party 343 kB · 4 req

Third parties 3 entities

343 kB transferred, 78 ms of main thread time. This is the number most likely to regress without anyone on your team shipping anything.

Google Tag Manager 322 kB · 66 ms CPU

Google Analytics 20.9 kB · 12 ms CPU

Other Google APIs/SDKs 21 B · 0 ms CPU

Page health

Metric	Current	Previous	Change	Best	Worst
Main Thread Work	989 ms	—	—	989 ms	989 ms
Long Tasks	3	—	—	3	3
DOM Elements	383	—	—	383	383
Axe Violations Violating nodes from a full axe run — stricter than Lighthouse's subset	16	—	—	16	16
A11y Failures	4	—	—	4	4
A11y Failing Nodes	16	—	—	16	16

Main thread work

script evaluation 484 ms

other 322 ms

style layout 79 ms

script parse compile 46 ms

paint composite render 28 ms

parse HTML 17 ms

garbage collection 13 ms

Axe violations axe-core 4.13.0, full rule set

16 violating nodes across 5 rules, 584 passing. This is a standalone axe run, stricter than the subset Lighthouse folds into its score above — and it is the second tiebreaker in the ranking.

critical image-alt — Images must have alternative text 6 nodes
serious link-name — Links must have discernible text 6 nodes
minor aria-allowed-role — ARIA role should be appropriate for the element 2 nodes
moderate landmark-unique — Landmarks should have a unique role or role/label/title (i.e. accessible name) combination 1 node
moderate region — All page content should be contained by landmarks 1 node

Accessibility failures 4 of 31 audits

Tracked as a count, not just the score — the weighted score is coarse enough that you can ship a broken component and barely move it.

image-alt — Image elements do not have `[alt]` attributes 6 nodes
link-name — Links do not have a discernible name 6 nodes
target-size — Touch targets do not have sufficient size or spacing. 3 nodes
label-content-name-mismatch — Elements with visible text labels do not have matching accessible names. 1 node

Hygiene

Changes rarely — which is exactly why a change is worth noticing.

HTTPS HSTS CSP Clickjacking protection Origin isolation Trusted Types bfcache h2

Measurement log

Every stored run for this URL, newest first. Failures are kept as records — "this site was down on Tuesday" is data too.

When	Perf	LCP	CLS	TBT	Weight	Runs	Spread	Bench	Took
Aug 25, 2026, 4:36 PM UTC	94	2.88 s	0.011	147 ms	545 kB	3/3	±3	2,436	28s

When

Perf

LCP

CLS

TBT

Weight

Runs

Spread

Bench

Took

Aug 25, 2026, 4:36 PM UTC

2.88 s

0.011

147 ms

545 kB

3/3

±3

2,436

28s

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