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.
6.47 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
8.03 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
791 ms
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.
11.96 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.
54.55 s
Page Load Progression
FPage Weight BudgetAction11.6 MB transferred, 105 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
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
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
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
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
DJS Execution CostAction3157ms total JS executionFIX
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| Unattributable | 621ms | 17ms | 0ms | 3rd |
| https://isweb.co.kr/ | 595ms | 73ms | 5ms | 1st |
| https://www.googletagmanager.com/gtag/js?id=G-YSW21L2669 | 312ms | 234ms | 45ms | 3rd |
| https://www.googletagmanager.com/gtag/js?id=AW-10841925644 | 300ms | 253ms | 46ms | 3rd |
| https://isweb.co.kr/file/plugin/jquery.ui/jquery-ui.js | 225ms | 38ms | 43ms | 1st |
| https://isweb.co.kr/cdn-cgi/challenge-platform/scripts/jsd/main.js | 223ms | 211ms | 2ms | 1st |
| https://www.googletagmanager.com/gtm.js?id=GTM-T4QV2F8C | 173ms | 144ms | 27ms | 3rd |
| https://connect.facebook.net/en_US/fbevents.js | 118ms | 89ms | 29ms | 3rd |
| https://connect.facebook.net/signals/config/1484898934979788?v=2.9.303&r=stable&domain=isweb.co.kr&hme=97937018cefade17726f0472876fc101316b2ce9008a35a6a5a7977d7436151a&ex_m=104%2C205%2C154%2C22%2C72%2C73%2C145%2C68%2C67%2C11%2C162%2C90%2C16%2C138%2C127%2C39%2C75%2C78%2C134%2C159%2C164%2C8%2C4%2C5%2C7%2C6%2C3%2C91%2C101%2C165%2C170%2C219%2C62%2C186%2C187%2C55%2C276%2C30%2C74%2C231%2C230%2C229%2C23%2C33%2C103%2C61%2C10%2C63%2C97%2C98%2C99%2C105%2C130%2C31%2C29%2C132%2C133%2C129%2C128%2C155%2C76%2C158%2C156%2C157%2C50%2C60%2C123%2C15%2C161%2C45%2C263%2C264%2C262%2C26%2C27%2C28%2C48%2C146%2C77%2C112%2C18%2C20%2C44%2C40%2C42%2C41%2C83%2C92%2C96%2C110%2C144%2C147%2C46%2C111%2C24%2C21%2C119%2C69%2C36%2C149%2C148%2C150%2C141%2C139%2C25%2C35%2C59%2C109%2C160%2C70%2C17%2C152%2C114%2C81%2C66%2C19%2C85%2C86%2C116%2C84%2C136%2C135%2C34%2C278%2C293%2C212%2C201%2C202%2C200%2C296%2C288%2C52%2C213%2C107%2C131%2C80%2C121%2C54%2C47%2C49%2C113%2C120%2C126%2C58%2C64%2C151%2C115%2C37%2C32%2C53%2C56%2C100%2C163%2C1%2C124%2C14%2C122%2C12%2C2%2C57%2C93%2C65%2C118%2C89%2C88%2C166%2C167%2C94%2C95%2C9%2C125%2C102%2C51%2C142%2C87%2C79%2C71%2C117%2C106%2C43%2C143%2C0%2C82%2C137%2C140%2C153%2C38%2C108%2C13%2C168 | 104ms | 89ms | 14ms | 3rd |
| https://cdn.datamanager.co.kr/0/tcsdm.js?eid=1h823ex6u2ypg1h823ex6u | 84ms | 64ms | 11ms | 3rd |
Showing top 10 of 16 scripts
FJS BundlesAction28 scripts, 697 KB unusedFIX
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://www.googletagmanager.com/gtag/js?id=AW-10841925644&cx=c>m=4e64k0 | 178 KB | 115 KB (65%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtag/js?id=G-YSW21L2669&cx=c>m=4e64k0 | 177 KB | 115 KB (65%) | ✓ | 3rd |
| https://isweb.co.kr/file/plugin/froala/js/froala_editor.pkgd.min.js | 129 KB | 112 KB (87%) | ✓ | 1st |
| https://isweb.co.kr/file/plugin/jquery.ui/jquery-ui.js | 114 KB | 99 KB (87%) | ✗ | 1st |
| https://www.googletagmanager.com/gtag/js?id=G-YSW21L2669 | 177 KB | 69 KB (39%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-T4QV2F8C | 124 KB | 62 KB (50%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtag/js?id=AW-10841925644 | 178 KB | 60 KB (34%) | ✓ | 3rd |
| https://connect.facebook.net/en_US/fbevents.js | 97 KB | 34 KB (36%) | ✓ | 3rd |
| https://isweb.co.kr/file/renew/js/swiper.min.js | 35 KB | 31 KB (89%) | ✗ | 1st |
| https://isweb.co.kr/file/plugin/froala/js/languages/ko.js | 4 KB | — | ✓ | 1st |
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
DPage Weight InventoryAction105 resources · 11.6 MB · 697 KB savings availableFIX
~696.6 KiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 105 resources | 11.6 MiB | ||||||
FHTTP CachingActionNo cache headersFIX
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
CImage OptimizationAction24 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
A+Third-Party Impact11% third-party, 0 ms blockingPASS
A+Text CompressionAll text resources are compressedPASS
A+Font Loading4 fonts (4570 KB)PASS
Web fonts
4
4570 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 ~3656 KB and ~7312 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
A+Green HostingWhether the site is served from green-energy infrastructurePASS
Green Hosting
This site is hosted on green energy infrastructure
Provider: Cloudflare
Network Waterfall105 requests over 10937msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
Unattributable Unattributable | Other | 621ms | 0 KB | — | ₩2452/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 312ms | 177 KB | 39% | ₩1234/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 300ms | 178 KB | 34% | ₩1184/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 173ms | 124 KB | 50% | ₩681/mo | Costly |
Facebook Pixel connect.facebook.net | Advertising | 118ms | 97 KB | 36% | ₩467/mo | Costly |
Facebook Pixel connect.facebook.net | Advertising | 104ms | 45 KB | — | ₩411/mo | Costly |
cdn.datamanager.co.kr cdn.datamanager.co.kr | Other | 84ms | 31 KB | — | ₩330/mo | Costly |
Google Fonts fonts.googleapis.com | Font | 75ms | 204 KB | — | ₩296/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 68ms | 177 KB | 65% | ₩270/mo | Costly |
ssl.pstatic.net ssl.pstatic.net | Other | 63ms | 18 KB | — | ₩250/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 63ms | 178 KB | 65% | ₩247/mo | Costly |
These scripts may cost more than they're worth
- Unattributable adds 621ms and costs ~₩2452/month
- Google Tag Manager adds 312ms and costs ~₩1234/month
- Google Tag Manager adds 300ms and costs ~₩1184/month
- Google Tag Manager adds 173ms and costs ~₩681/month
- Facebook Pixel adds 118ms and costs ~₩467/month
- Facebook Pixel adds 104ms and costs ~₩411/month
- cdn.datamanager.co.kr adds 84ms and costs ~₩330/month
- Google Fonts adds 75ms and costs ~₩296/month
- Google Tag Manager adds 68ms and costs ~₩270/month
- ssl.pstatic.net adds 63ms and costs ~₩250/month
- Google Tag Manager adds 63ms and costs ~₩247/month
63% of JavaScript execution time comes from third-party scripts.
Third-party scripts (analytics, ads, social, A/B testing) often dominate execution time — every one is a perf-and-privacy tax.
Learn more ▾ ▴
Each third-party script is a black box: you don't control when it loads, what it executes, or how much it grows. They often account for a major share of total blocking time on average sites (HTTP Archive's Web Almanac documents the trend). Audit which ones you actually need, defer the rest, and use facade patterns (lite-youtube, lite-vimeo) for embedded media.
Source: web.dev / HTTP Archive Web Almanac
Unattributable takes 621ms 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 312ms 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 300ms 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 173ms 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 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
Facebook Pixel takes 118ms 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
Facebook Pixel takes 104ms 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
cdn.datamanager.co.kr takes 84ms 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 Fonts takes 75ms 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 68ms 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
65% 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
ssl.pstatic.net takes 63ms 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 63ms 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
65% 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