Performance
· 17 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.Performance-focused optimization plan with CWV assessment, top offenders, and time estimates
First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.
28.04 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
37.52 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
1.28 s
Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.
0.134
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
28.04 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.
43.65 s
Page Load Progression
FPage Weight BudgetAction8.7 MB transferred, 153 requestsFIX
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
JavaScript bundle is large — code-split routes and lazy-load off-screen components to defer.
Source: web.dev
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
Image bandwidth is high — modern formats (WebP/AVIF) and resizing typically cut it 50%+.
Source: web.dev
Remove unused CSS rules with tools like PurgeCSS to reduce stylesheet size.
CSS bundle is large — purge unused styles (PurgeCSS, Tailwind JIT) to reduce CSS payload.
Source: web.dev
Subset fonts to include only used characters, or switch to system font stacks.
Font payload is large — subset to used glyphs only, or fall back to system fonts (zero load time).
Source: web.dev font loading
Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.
High HTTP request count — bundling, sprite-ing, and HTTP/2 server push can reduce per-request overhead.
Source: web.dev
DThird-Party ImpactAction100% third-party, 0 ms blockingFIX
FJS Execution CostAction6175ms total JS executionFIX
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://sf16-sg.larksuitecdn.com/obj/suite-public-file-sg/hera_tmp/hera/comp.a3dc50fafdb56593f3e943ffa.js | 2122ms | 1012ms | 1043ms | 3rd |
| https://sf16-sg.larksuitecdn.com/obj/suite-public-file-sg/open_file/resources/hera-static/js/index.59d01f39e002c74fc6724715629b60b642efcfb7338c573ea2bf10117d8bd877.js | 1105ms | 695ms | 129ms | 3rd |
| Unattributable | 760ms | 13ms | 0ms | 3rd |
| https://www.larksuite.com/en_sg/?from_site=feishu | 666ms | 65ms | 9ms | 3rd |
| /index.59d01f39e002c74fc6724715629b60b642efcfb7338c573ea2bf10117d8bd877.js | 645ms | 124ms | 0ms | 3rd |
| https://lf-package-sg.larksuitecdn.com/obj/lark-static-sgsaas/lark/passport/tenant/tenant-widget-6.1.2-1.0.0.143.js | 174ms | 114ms | 59ms | 3rd |
| https://sf16-sg.larksuitecdn.com/obj/suite-public-file-sg/hera_tmp/hera/comp.a3dc50fafdb56593f3e943ffa.css | 128ms | 0ms | 0ms | 3rd |
| https://sf16-sg.larksuitecdn.com/obj/suite-public-file-sg/vendor/vendor.6b3fe94d8606.js | 117ms | 88ms | 17ms | 3rd |
| https://accounts.google.com/gsi/client | 116ms | 50ms | 63ms | 3rd |
| https://lf-package-sg.larksuitecdn.com/obj/lark-static-sgsaas/lark/iam/passport-js-apis-plugin-google-2.1.3.js | 98ms | 57ms | 40ms | 3rd |
Showing top 10 of 13 scripts
FJS BundlesAction12 scripts, 2.7 MB unusedFIX
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://sf16-sg.larksuitecdn.com/obj/suite-public-file-sg/hera_tmp/hera/comp.a3dc50fafdb56593f3e943ffa.js | 3319 KB | 2283 KB (69%) | ✓ | 3rd |
| https://sf16-sg.larksuitecdn.com/obj/suite-public-file-sg/open_file/resources/hera-static/js/index.59d01f39e002c74fc6724715629b60b642efcfb7338c573ea2bf10117d8bd877.js | 310 KB | 153 KB (50%) | ✓ | 3rd |
| https://lf-package-sg.larksuitecdn.com/obj/lark-static-sgsaas/lark/passport/tenant/tenant-widget-6.1.2-1.0.0.143.js | 202 KB | 119 KB (60%) | ✓ | 3rd |
| https://lf-package-sg.larksuitecdn.com/obj/lark-static-sgsaas/lark/iam/passport-js-apis-plugin-google-2.1.3.js | 114 KB | 84 KB (74%) | ✓ | 3rd |
| https://accounts.google.com/gsi/client | 96 KB | 72 KB (75%) | ✓ | 3rd |
| https://sf16-sg.larksuitecdn.com/obj/suite-public-file-sg/vendor/vendor.6b3fe94d8606.js | 68 KB | 30 KB (44%) | ✓ | 3rd |
| https://sf16-sg.larksuitecdn.com/obj/suite-public-file-sg/vendor/polyfill.min.js | 35 KB | — | ✓ | 3rd |
| https://lf-package-sg.larksuitecdn.com/obj/lark-static-sgsaas/lark/iam/passport-js-apis-2.2.1-1.0.0.78.js | 21 KB | — | ✓ | 3rd |
| https://lf-package-sg.larksuitecdn.com/obj/lark-static-sgsaas/lmp/cookie/banner-sdk.1.4.3.js | 38 KB | — | ✓ | 3rd |
| https://sf16-short-sg.bytedapm.com/slardar/fe/sdk-web/browser.sg.js?bid=larksuite_browser&globalName=Slardar | 17 KB | — | ✓ | 3rd |
Consider code splitting or tree shaking to reduce unused code.
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.
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.
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.
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.
This bundle has high unused code — code-split or tree-shake to ship only what executes.
Source: web.dev / Lighthouse coverage
FPage Weight InventoryAction153 resources · 8.7 MB · 2.7 MB savings availableFIX
~2.7 MiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 153 resources | 8.7 MiB | ||||||
FHTTP CachingActionNo cache headersFIX
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
CImage OptimizationAction110 images, 0 KB saveableREVIEW
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
CGreen HostingActionWhether the site is served from green-energy infrastructureREVIEW
Green Hosting
No green hosting detected
A+Text CompressionAll text resources are compressedPASS
A+Font Loading4 fonts (424 KB)PASS
Web fonts
4
424 KB total
Render-blocking
0
of 4
Dominant font-display
swap
Most common across fonts
Font loading timeline
- Convert to woff2 for ~30% smaller file size
- Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
- Convert to woff2 for ~30% smaller file size
- Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
- Convert to woff2 for ~30% smaller file size
- Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
- Convert to woff2 for ~30% smaller file size
- Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
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)
Fixing the unchecked items could save ~339 KB and ~678 ms
A+Resource CachingAll resources properly cachedPASS
A+Critical Rendering PathNo render-blocking resourcesPASS
A+Resource HintsNo optimization neededPASS
A+Render-Blocking ResourcesNo render-blocking resources detectedPASS
A+Third-Party ResourcesNo third-party resources detectedPASS
Network Waterfall153 requests over 5333msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
sf16-sg.larksuitecdn.com sf16-sg.larksuitecdn.com | Other | 2122ms | 3319 KB | 69% | ¥284/mo | Costly |
sf16-sg.larksuitecdn.com sf16-sg.larksuitecdn.com | Other | 1105ms | 310 KB | 50% | ¥148/mo | Costly |
Unattributable Unattributable | Other | 760ms | 0 KB | — | ¥102/mo | Costly |
www.larksuite.com www.larksuite.com | Other | 666ms | 63 KB | — | ¥89/mo | Costly |
/index.59d01f39e002c74fc6724715629b60b642efcfb7338c573ea2bf10117d8bd877.js /index.59d01f39e002c74fc6724715629b60b642efcfb7338c573ea2bf10117d8bd877.js | Other | 645ms | 0 KB | — | ¥86/mo | Costly |
lf-package-sg.larksuitecdn.com lf-package-sg.larksuitecdn.com | Other | 174ms | 202 KB | 60% | ¥23/mo | Optional |
sf16-sg.larksuitecdn.com sf16-sg.larksuitecdn.com | Other | 128ms | 417 KB | — | ¥17/mo | Optional |
sf16-sg.larksuitecdn.com sf16-sg.larksuitecdn.com | Other | 117ms | 68 KB | 44% | ¥16/mo | Optional |
accounts.google.com accounts.google.com | Other | 116ms | 96 KB | 75% | ¥16/mo | Optional |
lf-package-sg.larksuitecdn.com lf-package-sg.larksuitecdn.com | Other | 98ms | 114 KB | 74% | ¥13/mo | Optional |
sf16-short-sg.bytedapm.com sf16-short-sg.bytedapm.com | Other | 85ms | 17 KB | — | ¥11/mo | Optional |
lf-package-sg.larksuitecdn.com lf-package-sg.larksuitecdn.com | Other | 84ms | 38 KB | — | ¥11/mo | Optional |
sf16-sg.larksuitecdn.com sf16-sg.larksuitecdn.com | Other | 76ms | 35 KB | — | ¥10/mo | Optional |
These scripts may cost more than they're worth
- sf16-sg.larksuitecdn.com adds 2122ms and costs ~¥284/month
- sf16-sg.larksuitecdn.com adds 1105ms and costs ~¥148/month
- Unattributable adds 760ms and costs ~¥102/month
- www.larksuite.com adds 666ms and costs ~¥89/month
- /index.59d01f39e002c74fc6724715629b60b642efcfb7338c573ea2bf10117d8bd877.js adds 645ms and costs ~¥86/month
100% of JavaScript execution time is spent on third-party scripts. Consider auditing which scripts are essential.
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
sf16-sg.larksuitecdn.com takes 2122ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
69% of sf16-sg.larksuitecdn.com's code is unused. The script may be loading features you don't use.
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev
sf16-sg.larksuitecdn.com takes 1105ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
50% of sf16-sg.larksuitecdn.com's code is unused. The script may be loading features you don't use.
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev
Unattributable takes 760ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
www.larksuite.com takes 666ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
/index.59d01f39e002c74fc6724715629b60b642efcfb7338c573ea2bf10117d8bd877.js takes 645ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
60% of lf-package-sg.larksuitecdn.com's code is unused. The script may be loading features you don't use.
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev
75% of accounts.google.com's code is unused. The script may be loading features you don't use.
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev
74% of lf-package-sg.larksuitecdn.com's code is unused. The script may be loading features you don't use.
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev