Performance
· 15 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.
1.80 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
4.73 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
0 ms
Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.
0.130
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
3.02 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.
4.74 s
Page Load Progression
651 ms 1.3 s 2.0 s 2.6 s
3.3 s 3.9 s
4.6 s
5.2 sFPage Weight BudgetAction16.8 MB transferred, 61 requestsFIX
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
DThird-Party ImpactAction100% third-party, 0 ms blockingFIX
DPage Weight InventoryAction61 resources · 16.8 MB · 190 KB savings availableFIX
~189.8 KiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 61 resources | 16.8 MiB | ||||||
CImage OptimizationAction34 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
BJS Execution Cost554ms total JS executionREVIEW
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://www.mynavi.jp/ | 267ms | 5ms | 0ms | 3rd |
| Unattributable | 158ms | 17ms | 0ms | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-WNZ67J | 64ms | 50ms | 9ms | 3rd |
| https://cdn-au.onetrust.com/scripttemplates/6.31.0/otBannerSdk.js | 64ms | 38ms | 10ms | 3rd |
CJS BundlesAction12 scripts, 190 KB unusedREVIEW
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://www.googletagmanager.com/gtm.js?id=GTM-WNZ67J | 139 KB | 75 KB (54%) | ✓ | 3rd |
| https://connect.facebook.net/ja_JP/bundle/sdk.js/ | 78 KB | 54 KB (70%) | ✓ | 3rd |
| https://cdn-au.onetrust.com/scripttemplates/6.31.0/otBannerSdk.js | 79 KB | 40 KB (50%) | ✓ | 3rd |
| https://www.mynavi.jp/wp-content/themes/site/assets/js/plugin/swiper/swiper-bundle.min.js?ver=6.9.4 | 39 KB | 21 KB (55%) | ✓ | 3rd |
| https://www.mynavi.jp/wp-content/themes/site/assets/js/jquery.min.js?ver=3.3.1 | 30 KB | — | ✓ | 3rd |
| https://www.mynavi.jp/wp-content/themes/site/assets/js/plugin/slick/slick.min.js?ver=6.9.4 | 10 KB | — | ✓ | 3rd |
| https://www.mynavi.jp/wp-content/themes/site/assets/js/plugin/fitie-master/fitie.js?ver=6.9.4 | 1 KB | — | ✓ | 3rd |
| https://www.mynavi.jp/wp-content/themes/site/assets/js/script.js?ver=20260420110036 | 4 KB | — | ✓ | 3rd |
| https://cdn-au.onetrust.com/scripttemplates/otSDKStub.js | 9 KB | — | ✓ | 3rd |
| https://cdn-au.onetrust.com/consent/5646b044-8952-4657-902b-e6b0000d2c03/5646b044-8952-4657-902b-e6b0000d2c03.json | 2 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
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 Loading1 fonts (2 KB)PASS
Web fonts
1
2 KB total
Render-blocking
0
of 1
Dominant font-display
swap
Most common across fonts
Font loading timeline
- Convert to woff2 for ~30% smaller file size
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 CachingAll resources properly cachedPASS
A+Critical Rendering PathNo render-blocking resourcesPASS
A+Resource HintsNo optimization neededPASS
AHTTP Cachingmax-age=3600 (1 hour)PASS
max-age=3600
| Directive | Value | Meaning |
|---|---|---|
| max-age | 3600 | Cache for 1 hour |
Network Waterfall61 requests over 5217msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
www.mynavi.jp www.mynavi.jp | Other | 267ms | 9 KB | — | ¥369/mo | Costly |
Unattributable Unattributable | Other | 158ms | 0 KB | — | ¥218/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 64ms | 139 KB | 54% | ¥89/mo | Costly |
cdn-au.onetrust.com cdn-au.onetrust.com | Other | 64ms | 79 KB | 50% | ¥88/mo | Costly |
These scripts may cost more than they're worth
- www.mynavi.jp adds 267ms and costs ~¥369/month
- Unattributable adds 158ms and costs ~¥218/month
- Google Tag Manager adds 64ms and costs ~¥89/month
- cdn-au.onetrust.com adds 64ms and costs ~¥88/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
www.mynavi.jp takes 267ms 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
Unattributable takes 158ms 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
Google Tag Manager takes 64ms 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
54% of Google Tag Manager'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
cdn-au.onetrust.com takes 64ms 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 cdn-au.onetrust.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