vitest.dev

Ranks Overall #1,426 Developer Tooling #50 Test Runners #8

Data from Oct 9, 2026, 10:09 AM UTC 3d old, older than this category's 3 days freshness target Measured every 2 days · 20 runs since Aug 27, 2026

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

This data is 3d old.

Sites are measured on a rolling schedule, so figures here are the newest successful measurement rather than a reading taken just now. Comparisons against other sites may span different points in time.

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

Stack

Built with VitePress 2.0.0

Uses Vue 3.5.42

Hosted by Netlify

Filmstrip LAB Throttled

How the page drew during the measured load, at 8 points across 9.96 s. Compare this filmstrip against another site.

1.25 s
2.37 s
3.73 s
4.98 s
6.22 s
7.47 s
8.71 s
9.96 s

Lighthouse Scores LAB Simulated

Performance

no change

Accessibility

no change

100

Best Practices

no change

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 (2026-09-10 → 2026-10-07), url-level.

Metric	Lab Simulated	Field
LCP CWV Largest Contentful Paint	4.52 s poor	↓ -8 ms (-0.2%) 4.52 s – 8.21 s	2.18 s good	80.5% 12.5% 7%
INP CWV Interaction to Next Paint — field only, no lab run can measure it	n/a	—	131 ms good	89.8% 7.4% 2.8%
CLS CWV Cumulative Layout Shift	0.021 good	→ no change 0.021 – 0.021	0 good	98.9% 0.8% 0.3%
TBT Total Blocking Time	210 ms needs work	↑ +19 ms (+9.9%) 20 ms – 350 ms	n/a	—
FCP First Contentful Paint	2.27 s needs work	↓ -8 ms (-0.4%) 2.25 s – 3.27 s	1.45 s good	84% 10.2% 5.8%
Speed Index	2.27 s good	↓ -8 ms (-0.4%) 2.25 s – 3.27 s	n/a	—
TTFB Time to First Byte	620 ms good	↓ -8 ms (-1.3%) 603 ms – 642 ms	725 ms good	77.4% 16.2% 6.4%

Metric

Lab Simulated

Field

Value

Change / range

Trend

p75

Distribution

LCP CWV Largest Contentful Paint

4.52 s poor

↓ -8 ms (-0.2%) 4.52 s – 8.21 s

2.18 s good

80.5% 12.5% 7%

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

n/a

—

131 ms good

89.8% 7.4% 2.8%

CLS CWV Cumulative Layout Shift

0.021 good

→ no change 0.021 – 0.021

0 good

98.9% 0.8% 0.3%

TBT Total Blocking Time

210 ms needs work

↑ +19 ms (+9.9%) 20 ms – 350 ms

n/a

—

FCP First Contentful Paint

2.27 s needs work

↓ -8 ms (-0.4%) 2.25 s – 3.27 s

1.45 s good

84% 10.2% 5.8%

Speed Index

2.27 s good

↓ -8 ms (-0.4%) 2.25 s – 3.27 s

n/a

—

TTFB Time to First Byte

620 ms good

↓ -8 ms (-1.3%) 603 ms – 642 ms

725 ms good

77.4% 16.2% 6.4%

LCP Subparts LAB Throttled

The subparts attribute LCP to your server, resource discovery, download, or rendering. They come from one throttled load, the same one as the filmstrip, so they add up to that load’s LCP rather than the simulated Lab LCP above.

resource load duration 2.69 s

resource load delay 1.69 s

time to first byte 583 ms

element render delay 48 ms

LCP LAB Simulated vs LCP FIELD

Lab 4.52 s

Field p75 2.18 s

The lab LCP is 2.07× the field p75 — real users likely have above-average hardware or network connectivity.

Page weight

Metric	Value	Change / range
Page Weight	1.46 MB	↑ +145 B 1.46 MB – 1.47 MB
Requests	57	→ no change 57 – 58
Third-party Weight	3.4 kB	↓ -10 B (-0.3%) 3.4 kB – 7.5 kB
Third-party CPU	0 ms	→ no change 0 ms – 2 ms
Unused JS	25.4 kB	↑ +52 B (+0.2%) 25.3 kB – 46.6 kB
Unused CSS	0 B	→ no change 0 B – 0 B

Metric

Value

Change / range

Trend

Page Weight

1.46 MB

↑ +145 B 1.46 MB – 1.47 MB

Requests

→ no change 57 – 58

Third-party Weight

3.4 kB

↓ -10 B (-0.3%) 3.4 kB – 7.5 kB

Third-party CPU

0 ms

→ no change 0 ms – 2 ms

Unused JS

25.4 kB

↑ +52 B (+0.2%) 25.3 kB – 46.6 kB

Unused CSS

0 B

→ no change 0 B – 0 B

By resource type

Type	Share	Size	Requests
image	52.7%	770 kB	22
other	21.2%	310 kB	10
font	12.9%	188 kB	4
script	9.3%	137 kB	8
stylesheet	3.4%	49.9 kB	3
document	0.5%	7.1 kB	1
Total		1.46 MB	57

Third parties 2 entities

Entity	Transfer	Size	Main thread Simulated
iconify.design	other	2.5 kB	0 ms
Google Fonts	stylesheet	925 B	0 ms
Total		3.4 kB	0 ms

Entity

Transfer

Size

Main thread Simulated

iconify.design

other

2.5 kB

0 ms

Google Fonts

stylesheet

925 B

0 ms

Total

3.4 kB

0 ms

Without JavaScript

The same load, photographed twice at 412×823: once with scripts disabled, once as rendered.

0.7% of pixels differ — they are nearly identical. A shifted layout counts as difference, so a <noscript> banner alone can account for a large figure.

Page health

Metric	Value	Change / range
Main Thread Work	1.70 s	↑ +98 ms (+6.1%) 1.01 s – 2.03 s
Long Tasks	5	→ no change 1 – 6
DOM Elements	321	→ no change 318 – 321
Axe Violations Violating nodes from a full Axe CLI run (more than Lighthouse reports)	28	→ no change 28 – 28
A11y Failures	2	→ no change 2 – 2
A11y Failing Nodes	3	→ no change 3 – 3

Metric

Value

Change / range

Trend

Main Thread Work

1.70 s

↑ +98 ms (+6.1%) 1.01 s – 2.03 s

Long Tasks

→ no change 1 – 6

DOM Elements

321

→ no change 318 – 321

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

→ no change 28 – 28

A11y Failures

→ no change 2 – 2

A11y Failing Nodes

→ no change 3 – 3

Main thread work

Task	Share	Duration Simulated
other	44%	748 ms
script evaluation	31%	520 ms
style layout	14%	246 ms
paint composite render	7%	115 ms
parse HTML	4%	68 ms
script parse compile	0%	4 ms
Total		1.70 s

Task

Time

Duration Simulated

other

44%

748 ms

script evaluation

31%

520 ms

style layout

14%

246 ms

paint composite render

115 ms

parse HTML

68 ms

script parse compile

4 ms

Total

1.70 s

Axe violations axe-core 4.13.0, full rule set

28 violating nodes across 3 rules, 374 passing. This is a standalone Axe CLI run and is stricter than the subset Lighthouse already includes.

moderate region — All page content should be contained by landmarks 25 nodes

Offending elements (5 of 25)

.md\:grid-cols-2

<div class="wrapper wrapper--ticks grid md:grid-cols-2 w-full border-nickel divide-x" data-v-83c11088="">

.max-w-md.gap-3.flex-col > .gap-3.items-center.flex

<div class="flex gap-3 items-center"><img src="/assets/vitest-light.BeSPX0d3.svg" alt="Vitest icon" class="size-5"><span class="text-grey text-xs font-medium font-mono uppercase tracking-wide">Why Vi…

.max-w-md.gap-3.flex-col > h3

<h3 class="text-white max-w-xl text-balance">The Vite Native Test Runner</h3>

.lg\:max-w-lg
```
<div class="lg:max-w-lg">
```

.sm\:py-28

<section class="wrapper border-t px-5 sm:px-10 py-14 sm:py-28 flex flex-col justify-center gap-3 text-center items-center"><h2 class="text-white max-w-2xl text-balance text-center">Fast. Lightweight.…

moderate heading-order — Heading levels should only increase by one 2 nodes

Offending elements

.max-w-md.gap-3.flex-col > h3

<h3 class="text-white max-w-xl text-balance">The Vite Native Test Runner</h3>

.sm\:text-pretty

<h5 class="text-balance sm:text-pretty text-white" data-v-bcdb385d="">Vite Powered</h5>

moderate landmark-one-main — Document should have one main landmark 1 node
Offending element
1. html
```
<html lang="en-US" dir="ltr" data-variant="vitest" data-theme="dark">
```

Accessibility failures 2 of 21 audits

heading-order — Heading elements are not in a sequentially-descending order 2 nodes
landmark-one-main — Document does not have a main landmark. 1 node

Best Practices failures 1 of 18 audits

valid-source-maps — Missing source maps for large first-party JavaScript 1 item

SEO failures 1 of 9 audits

link-text — Links do not have descriptive text 2 items

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
2026-10-03	2.22 s	131 ms	1.62 s	824 ms
2026-09-26	2.16 s	115 ms	1.56 s	796 ms
2026-09-19	2.06 s	115 ms	1.38 s	701 ms
2026-09-12	1.89 s	113 ms	1.29 s	624 ms
2026-09-05	1.78 s	111 ms	1.21 s	572 ms
2026-08-29	1.65 s	123 ms	1.22 s	539 ms
2026-08-22	1.66 s	128 ms	1.26 s	565 ms
2026-08-15	1.84 s	140 ms	1.36 s	628 ms
2026-08-08	1.91 s	144 ms	1.37 s	686 ms
2026-08-01	1.95 s	140 ms	1.40 s	705 ms
2026-07-25	2.07 s	132 ms	1.46 s	741 ms
2026-07-18	2.09 s	128 ms	1.48 s	727 ms

Week ending

LCP

INP

CLS

FCP

TTFB

2026-10-03

2.22 s

131 ms

1.62 s

824 ms

2026-09-26

2.16 s

115 ms

1.56 s

796 ms

2026-09-19

2.06 s

115 ms

1.38 s

701 ms

2026-09-12

1.89 s

113 ms

1.29 s

624 ms

2026-09-05

1.78 s

111 ms

1.21 s

572 ms

2026-08-29

1.65 s

123 ms

1.22 s

539 ms

2026-08-22

1.66 s

128 ms

1.26 s

565 ms

2026-08-15

1.84 s

140 ms

1.36 s

628 ms

2026-08-08

1.91 s

144 ms

1.37 s

686 ms

2026-08-01

1.95 s

140 ms

1.40 s

705 ms

2026-07-25

2.07 s

132 ms

1.46 s

741 ms

2026-07-18

2.09 s

128 ms

1.48 s

727 ms

Runs

Every stored run for this URL, newest first.

When	Perf	LCP	CLS	TBT	Weight	Runs	Spread	Bench	Took	Archive
Oct 9, 2026, 10:09 AM UTC	78	4.52 s	0.021	210 ms	1.46 MB	3/3	±11	2,301 -7%	63.8s	Wayback
Oct 7, 2026, 2:08 AM UTC	78	4.53 s	0.021	191 ms	1.46 MB	3/3	±10	2,370 -5%	63.6s	Wayback
Oct 3, 2026, 8:55 PM UTC	80	4.52 s	0.021	128 ms	1.46 MB	3/3	±7	2,899 +17%	57.2s	Wayback
Oct 1, 2026, 2:18 PM UTC	71	5.63 s	0.021	156 ms	1.46 MB	2/3	±4	2,689 +8%	57.2s	Wayback
Sep 29, 2026, 11:25 AM UTC	80	4.52 s	0.021	130 ms	1.46 MB	3/3	±7	2,735 +10%	56.7s	Wayback
Sep 25, 2026, 4:43 PM UTC	81	4.52 s	0.021	119 ms	1.46 MB	3/3	±5	2,977 +20%	57.6s	Wayback
Sep 23, 2026, 11:00 AM UTC	74	5.63 s	0.021	198 ms	1.46 MB	3/3	±2	2,256 -9%	64.1s	Wayback
Sep 21, 2026, 7:49 AM UTC	66	8.21 s	0.021	190 ms	1.46 MB	2/3	±2	2,446 -2%	62.5s	Wayback
Sep 18, 2026, 1:46 PM UTC	70	5.78 s	0.021	222 ms	1.46 MB	2/3	±2	2,218 -11%	62.9s	Wayback
Sep 16, 2026, 9:18 AM UTC	81	4.52 s	0.021	98 ms	1.46 MB	3/3	±3	4,188 +68%	51.8s	Wayback
Sep 14, 2026, 6:04 AM UTC	78	4.52 s	0.021	228 ms	1.46 MB	3/3	±11	2,145 -14%	66.1s	Wayback
Sep 11, 2026, 11:21 PM UTC	72	5.80 s	0.021	235 ms	1.46 MB	3/3	±4	2,342 -6%	64.5s	Wayback
Sep 9, 2026, 10:57 PM UTC	68	8.13 s	0.021	110 ms	1.46 MB	3/3	±26	2,336 -6%	39.1s	Wayback
Sep 7, 2026, 10:31 PM UTC	80	4.52 s	0.021	125 ms	1.46 MB	3/3	±19	2,979 +20%	29.3s	Wayback
Sep 5, 2026, 3:55 PM UTC	80	4.54 s	0.021	143 ms	1.46 MB	3/3	±38	3,180 +28%	29.2s	Wayback
Sep 4, 2026, 10:55 AM UTC	77	4.54 s	0.021	243 ms	1.46 MB	3/3	±26	2,567 +3%	30.6s	Wayback
Sep 3, 2026, 1:13 AM UTC	73	5.93 s	0.021	182 ms	1.46 MB	3/3	±6	2,481 0%	34.7s	Wayback
Sep 1, 2026, 11:26 PM UTC	80	4.76 s	0.021	20 ms	1.47 MB	3/3	±36	3,364 +35%	27.6s	Wayback
Aug 31, 2026, 10:31 PM UTC	67	6.00 s	0.021	350 ms	1.47 MB	2/3	±6	2,463 -1%	29.4s	Wayback
Aug 27, 2026, 6:59 PM UTC	80	4.75 s	0.021	69 ms	1.47 MB	3/3	±31	2,366 -5%	31.7s	Wayback

When

Scores

Perf

LCP

CLS

TBT

Weight

Runs

Spread

Bench

Took

Stack

Filmstrip LAB 🐢 Throttled

Lighthouse Scores LAB 🤖 Simulated

Metrics LAB FIELD

LCP Subparts LAB 🐢 Throttled

LCP LAB 🤖 Simulated vs LCP FIELD

Page weight

By resource type

Third parties 2 entities

Without JavaScript

Page health

Main thread work

Axe violations axe-core 4.13.0, full rule set

Accessibility failures 2 of 21 audits

Best Practices failures 1 of 18 audits

SEO failures 1 of 9 audits

Hygiene

Measurement log

Field history 25 weeks

Runs

Filmstrip LAB Throttled

Lighthouse Scores LAB Simulated

LCP Subparts LAB Throttled

LCP LAB Simulated vs LCP FIELD