Performance

· 17 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.

SCORE

GRADE

FIX

REVIEW

PASS

INFO

Performance-focused optimization plan with CWV assessment, top offenders, and time estimates

Mobile Desktop

Performance

Accessibility

Best Practices

SEO

First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.

2.99 s

Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.

5.88 s

Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.

3.18 s

Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.

0.000

Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.

9.62 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.

21.67 s

Page Load Progression

1.1 s

2.3 s

3.4 s

4.5 s

5.7 s

6.8 s

7.9 s

9.1 s

Checks

7 PASS 3 REVIEW 5 FIX

Page Weight Budget

Action

2.8 MB transferred, 320 requests

FIX

2.8 MB transferred, 320 requests

Page weighs 7.2 MB (2.8 MB transferred)

JavaScript is 990 KB — consider code splitting or lazy loading

Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.

Got: 990 KB

320 HTTP requests — consider bundling or reducing

Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.

Estimated 0.60 g CO2 per page load

2.8 MB transferred

320 requests

0.60 g CO2 per page load

JavaScript 990.3 KiB 34%

Other 953.0 KiB 33%

Images 732.2 KiB 25%

Fonts 119.5 KiB 4%

HTML 58.5 KiB 2%

Other 33.1 KiB 1%

CSS 19.4 KiB 1%

Other 6.8 KiB 0%

Other 3.0 KiB 0%

Other 0 B 0%

0 2.4 MB 4.9 MB

Over budget

Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.

Why this matters

JavaScript bundle is large — code-split routes and lazy-load off-screen components to defer.

Source: web.dev

Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.

Why this matters

High HTTP request count — bundling, sprite-ing, and HTTP/2 server push can reduce per-request overhead.

Source: web.dev

Third-Party Impact

Action

98% third-party, 0 ms blocking

FIX

98% third-party, 0 ms blocking

Third-party code accounts for 98% of page weight (2.8 MiB of 2.8 MiB)

Third-party blocking time is low (0 ms)

98%

First-party Third-party

JS Execution Cost

Action

13186ms total JS execution

FIX

13186ms total JS execution

https://icdn.lenta.ru/assets/webpack/vendorsOptiPw...: 4462ms CPU time

https://lenta.ru/: 1297ms CPU time

Unattributable: 1151ms CPU time

https://cdn-s01.rambler.ru/magic/v1.3.6/magic.js: 1098ms CPU time

https://yandex.ru/ads/system/context.js: 937ms CPU time

Third-party scripts: 11889ms (90% of total)

Main Thread Breakdown

Script Evaluation 50% Other 23% Style & Layout 18% Rendering 4% Script Parsing & Compilation 4%

Script	Total	Scripting	Parse/Compile	Party
https://icdn.lenta.ru/assets/webpack/vendorsOptiPwa.003d701c.js	4462ms	1688ms	52ms	3rd
https://lenta.ru/	1297ms	45ms	11ms	1st
Unattributable	1151ms	156ms	0ms	3rd
https://cdn-s01.rambler.ru/magic/v1.3.6/magic.js	1098ms	72ms	32ms	3rd
https://yandex.ru/ads/system/context.js	937ms	508ms	47ms	3rd
https://ssp.rambler.ru/capirs_async.js	878ms	730ms	56ms	3rd
https://privacy-cs.mail.ru/static/sync-loader.js	658ms	521ms	11ms	3rd
https://st.top100.ru/top100/top100.js	649ms	552ms	52ms	3rd
https://icdn.lenta.ru/assets/webpack/commonOptiPwa.003d701c.js	550ms	482ms	47ms	3rd
https://yastatic.net/partner-code-bundles/1304651/e98eb32840226dc3.js	348ms	237ms	31ms	3rd

Showing top 10 of 17 scripts

JS Bundles

Action

24 scripts, 387 KB unused

FIX

24 scripts, 387 KB unused

https://yastatic.net/partner-code-bundles/1304651/...: 93 KB unused (72%)

Consider code splitting or tree shaking to reduce unused code.

https://icdn.lenta.ru/assets/webpack/vendorsOptiPw...: 93 KB unused (71%)

Consider code splitting or tree shaking to reduce unused code.

https://yandex.ru/ads/system/context.js: 49 KB unused (47%)

Consider code splitting or tree shaking to reduce unused code.

https://mc.webvisor.org/metrika/tag_ww.js: 43 KB unused (50%)

Consider code splitting or tree shaking to reduce unused code.

https://ssp.rambler.ru/capirs_async.js: 36 KB unused (41%)

Consider code splitting or tree shaking to reduce unused code.

Total unused JavaScript: 387 KB

387 KB unused JavaScript

Downloaded but never executed on this page.

Script	Size	Unused	Minified	Party
https://yastatic.net/partner-code-bundles/1304651/00cc0164cd639ddf.js	130 KB	93 KB (72%)	✓	3rd
https://icdn.lenta.ru/assets/webpack/vendorsOptiPwa.003d701c.js	130 KB	93 KB (71%)	✓	3rd
https://yandex.ru/ads/system/context.js	105 KB	49 KB (47%)	✓	3rd
https://mc.webvisor.org/metrika/tag_ww.js	86 KB	43 KB (50%)	✓	3rd
https://ssp.rambler.ru/capirs_async.js	89 KB	36 KB (41%)	✓	3rd
https://st.top100.ru/top100/top100.js	37 KB	27 KB (74%)	✓	3rd
https://yastatic.net/partner-code-bundles/1304651/e98eb32840226dc3.js	58 KB	23 KB (40%)	✓	3rd
https://yastatic.net/partner-code-bundles/1304651/22d10f9d8e892aab.js	32 KB	23 KB (72%)	✓	3rd
https://www.tns-counter.ru/tcounter.js	0 KB	—	✓	3rd
https://privacy-cs.mail.ru/static/sync-loader.js	22 KB	—	✓	3rd

Consider code splitting or tree shaking to reduce unused code.

Why this matters

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.

Why this matters

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.

Why this matters

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.

Why this matters

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.

Why this matters

This bundle has high unused code — code-split or tree-shake to ship only what executes.

Source: web.dev / Lighthouse coverage

Page Weight Inventory

Action

320 resources · 2.8 MB · 387 KB savings available

FIX

320 resources · 2.8 MB · 387 KB savings available

Page weight 1.8 MB over 1MB target

Got: 2.8 MB Expected: ≤ 1 MB

~387 KB of savings available

317 third-party resources (98% of weight)

2 resources over 200KB

320 resources · 2.8 MiB · 317 third-party 1.8 MiB over 1MB target

JavaScript 35% · 1007.5 KiB

Other 33% · 948.2 KiB

Image 26% · 761.0 KiB

Font 4% · 119.5 KiB

Document 2% · 60.2 KiB

CSS 1% · 19.4 KiB

~386.8 KiB of savings available

Remove unused JavaScript: 386.8 KiB

#	Resource	Type	Size	Cache	Unused	3rd party	Issues

320 resources			2.8 MiB

Image Optimization

48 images, 0 KB saveable

REVIEW

48 images, 0 KB saveable

All images are well-optimized

48 images 732 KB

0 oversized -0 KB

40 legacy format

0 missing dimensions CLS risk

Green Hosting

Action

Whether the site is served from green-energy infrastructure

REVIEW

Green Hosting

No green hosting detected

HTTP Caching

max-age=0, private, must-revalidate

REVIEW

max-age=0, private, must-revalidate

Cache-Control header is set

Got: max-age=0, private, must-revalidate

ETag present — enables conditional (304) responses

Cache-Control

max-age=0, private, must-revalidate

Directive	Value	Meaning
max-age	0	Cache for 0 seconds
private	—	Only browser cache, not CDN/proxy
must-revalidate	—	Must recheck with server after expiry

A+

Text Compression

All text resources are compressed

PASS

All text resources are compressed

All text resources are properly compressed.

A+

Font Loading

3 fonts (120 KB)

PASS

3 fonts (120 KB)

3 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

120 KB total

Render-blocking

of 3

Dominant font-display

swap

Most common across fonts

Font loading timeline

Transfer FOIT (block) FOUT (swap)

lato-regular.20e7d22d.w... woff2 swap

Size 47 KB

Load time 537 ms

Start 1.8 s

Risk FOUT — text flashes from fallback to web font

lato-bold.accfe114.woff2 woff2 swap

Size 47 KB

Load time 578 ms

Start 1.8 s

Risk FOUT — text flashes from fallback to web font

text-variable-full.woff2 woff2 swap

Size 26 KB

Load time 36 ms

Start 3.8 s

Risk FOUT — text flashes from fallback to web font

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)

A+

Resource Caching

All resources properly cached

PASS

All resources properly cached

No caching issues found

All static resources have appropriate caching headers.

A+

Critical Rendering Path

No render-blocking resources

PASS

No render-blocking resources

No render-blocking resources detected

A+

Resource Hints

No optimization needed

PASS

No optimization needed

No resource hint issues

A+

Render-Blocking Resources

No render-blocking resources detected

PASS

No render-blocking resources detected

No render-blocking resources detected in <head>

A+

Third-Party Resources

No third-party resources detected

PASS

No third-party resources detected

Network Waterfall

320 requests over 6767ms

INFO

HTML JavaScript CSS Images Fonts XHR/Fetch Other

Third-Party Script Cost

Per-script blocking time, transfer cost, and cache headers

INFO

90% of JavaScript execution is third-party

First-party Third-party 11889ms · 962KB · ₽3520/mo

Script	Category	Execution	Transfer	Unused	Monthly Cost	Verdict
icdn.lenta.ru icdn.lenta.ru	Other	4462ms	130 KB	71%	₽1321/mo	Costly
Unattributable Unattributable	Other	1151ms	0 KB	—	₽341/mo	Costly
cdn-s01.rambler.ru cdn-s01.rambler.ru	Other	1098ms	43 KB	—	₽325/mo	Costly
yandex.ru yandex.ru	Other	937ms	105 KB	47%	₽277/mo	Costly
ssp.rambler.ru ssp.rambler.ru	Other	878ms	89 KB	41%	₽260/mo	Costly
privacy-cs.mail.ru privacy-cs.mail.ru	Other	658ms	22 KB	—	₽195/mo	Costly
st.top100.ru st.top100.ru	Other	649ms	37 KB	74%	₽192/mo	Costly
icdn.lenta.ru icdn.lenta.ru	Other	550ms	181 KB	—	₽163/mo	Costly
yastatic.net yastatic.net	Other	348ms	58 KB	40%	₽103/mo	Costly
mc.webvisor.org mc.webvisor.org	Other	325ms	86 KB	50%	₽96/mo	Costly
yastatic.net yastatic.net	Other	233ms	32 KB	72%	₽69/mo	Costly
vp.rambler.ru vp.rambler.ru	Other	187ms	18 KB	—	₽55/mo	Costly
yastatic.net yastatic.net	Other	183ms	130 KB	72%	₽54/mo	Costly
top-fwz1.mail.ru top-fwz1.mail.ru	Other	90ms	20 KB	—	₽27/mo	Optional
st.top100.ru st.top100.ru	Other	80ms	6 KB	—	₽24/mo	Optional
icdn.lenta.ru icdn.lenta.ru	Other	59ms	4 KB	—	₽18/mo	Optional

icdn.lenta.ru

Other

Costly

Execution 4462ms

Transfer 130 KB

Unused 71%

Monthly Cost ₽1321/mo

Unattributable

Other

Costly

Execution 1151ms

Transfer 0 KB

Monthly Cost ₽341/mo

cdn-s01.rambler.ru

Other

Costly

Execution 1098ms

Transfer 43 KB

Monthly Cost ₽325/mo

yandex.ru

Other

Costly

Execution 937ms

Transfer 105 KB

Unused 47%

Monthly Cost ₽277/mo

ssp.rambler.ru

Other

Costly

Execution 878ms

Transfer 89 KB

Unused 41%

Monthly Cost ₽260/mo

privacy-cs.mail.ru

Other

Costly

Execution 658ms

Transfer 22 KB

Monthly Cost ₽195/mo

st.top100.ru

Other

Costly

Execution 649ms

Transfer 37 KB

Unused 74%

Monthly Cost ₽192/mo

icdn.lenta.ru

Other

Costly

Execution 550ms

Transfer 181 KB

Monthly Cost ₽163/mo

yastatic.net

Other

Costly

Execution 348ms

Transfer 58 KB

Unused 40%

Monthly Cost ₽103/mo

mc.webvisor.org

Other

Costly

Execution 325ms

Transfer 86 KB

Unused 50%

Monthly Cost ₽96/mo

yastatic.net

Other

Costly

Execution 233ms

Transfer 32 KB

Unused 72%

Monthly Cost ₽69/mo

vp.rambler.ru

Other

Costly

Execution 187ms

Transfer 18 KB

Monthly Cost ₽55/mo

yastatic.net

Other

Costly

Execution 183ms

Transfer 130 KB

Unused 72%

Monthly Cost ₽54/mo

top-fwz1.mail.ru

Other

Optional

Execution 90ms

Transfer 20 KB

Monthly Cost ₽27/mo

st.top100.ru

Other

Optional

Execution 80ms

Transfer 6 KB

Monthly Cost ₽24/mo

icdn.lenta.ru

Other

Optional

Execution 59ms

Transfer 4 KB

Monthly Cost ₽18/mo

These scripts may cost more than they're worth

icdn.lenta.ru adds 4462ms and costs ~₽1321/month
Unattributable adds 1151ms and costs ~₽341/month
cdn-s01.rambler.ru adds 1098ms and costs ~₽325/month
yandex.ru adds 937ms and costs ~₽277/month
ssp.rambler.ru adds 878ms and costs ~₽260/month
privacy-cs.mail.ru adds 658ms and costs ~₽195/month
st.top100.ru adds 649ms and costs ~₽192/month
icdn.lenta.ru adds 550ms and costs ~₽163/month
yastatic.net adds 348ms and costs ~₽103/month
mc.webvisor.org adds 325ms and costs ~₽96/month
yastatic.net adds 233ms and costs ~₽69/month
vp.rambler.ru adds 187ms and costs ~₽55/month
yastatic.net adds 183ms and costs ~₽54/month

90% of JavaScript execution time is spent on third-party scripts. Consider auditing which scripts are essential.

Why this matters

When third-party JS execution time exceeds your own, performance gains from frontend work are capped by code you don't own.

Learn more ▾

Every millisecond of third-party JS competes with your own for main-thread time. If their share is bigger than yours, optimization on your code base barely moves the needle. Audit, defer, or remove third-parties before further frontend optimization. Use Lighthouse's third-party audit to identify the worst offenders.

Source: web.dev

icdn.lenta.ru takes 4462ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

71% of icdn.lenta.ru's code is unused. The script may be loading features you don't use.

Why this matters

Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.

Source: web.dev

Unattributable takes 1151ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

cdn-s01.rambler.ru takes 1098ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

yandex.ru takes 937ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

ssp.rambler.ru takes 878ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

privacy-cs.mail.ru takes 658ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

st.top100.ru takes 649ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

74% of st.top100.ru's code is unused. The script may be loading features you don't use.

Why this matters

Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.

Source: web.dev

icdn.lenta.ru takes 550ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

yastatic.net takes 348ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

mc.webvisor.org takes 325ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

50% of mc.webvisor.org's code is unused. The script may be loading features you don't use.

Why this matters

Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.

Source: web.dev

yastatic.net takes 233ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

72% of yastatic.net's code is unused. The script may be loading features you don't use.

Why this matters

Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.

Source: web.dev

vp.rambler.ru takes 187ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

yastatic.net takes 183ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

72% of yastatic.net's code is unused. The script may be loading features you don't use.

Why this matters

Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.

Source: web.dev

How third-party costs are calculated

All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.