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Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
72
GRADE
C
FIX
4
REVIEW
3
PASS
5
INFO
2

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

Mobile Desktop
58
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
96
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
100
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
100
SEO Measures basic SEO optimizations: meta tags, crawlability, link text, and mobile friendliness.

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

447 ms

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

1.65 s

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

754 ms

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

0.048

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

3.90 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.

3.95 s

Page Load Progression

797 ms
1.6 s
2.4 s
3.2 s
4.0 s
4.8 s
5.6 s
6.4 s
Checks
14
5 PASS 3 REVIEW 4 FIX
F
Page Weight Budget
Action
17.7 MB transferred, 149 requests
FIX
17.7 MB transferred, 149 requests
Critical::
Page weighs 23.4 MB (17.7 MB transferred)
Warning::
JavaScript is 2.0 MB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 2.0 MB
Warning::
149 HTTP requests — consider bundling or reducing
Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.
Info::
Estimated 3.7 g CO2 per page load
17.7 MB / 2.4 MB budget
17.7 MB transferred
149 requests
3.7 g CO2 per page load
Other 13.5 MiB 76%
JavaScript 2.0 MiB 11%
Other 1.4 MiB 8%
Images 377.1 KiB 2%
Fonts 177.2 KiB 1%
HTML 97.1 KiB 1%
CSS 72.9 KiB 0%
Other 8.1 KiB 0%
Other 2.6 KiB 0%
Other 2.0 KiB 0%
Other 292 B 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

D
Third-Party Impact
Action
90% third-party, 0 ms blocking
FIX
90% third-party, 0 ms blocking
Warning::
Third-party code accounts for 90% of page weight (15.9 MiB of 17.7 MiB)
Info::
Third-party blocking time is low (0 ms)
90%
First-party Third-party
F
JS Execution Cost
Action
4439ms total JS execution
FIX
4439ms total JS execution
Warning::
https://www.sanity.io/_next/static/chunks/0uz1gb6x...: 2883ms CPU time
Warning::
https://www.sanity.io/: 432ms CPU time
Warning::
Unattributable: 311ms CPU time
Warning::
https://www.sanity.io/_next/static/chunks/167ci08t...: 303ms CPU time
Info::
https://cmp.osano.com/16CLWDTCcnYWI2HHP/e53d2bde-3...: 235ms CPU time
Info::
Third-party scripts: 821ms (18% of total)

Main Thread Breakdown

Script Evaluation 62% Other 17% Style & Layout 10% Script Parsing & Compilation 5% Rendering 3%
ScriptTotalScriptingParse/CompileParty
https://www.sanity.io/_next/static/chunks/0uz1gb6x4i~gy.js?dpl=dpl_7XhRSfxibpajdLWaTbdePehnDSnS2883ms2189ms12ms1st
https://www.sanity.io/432ms19ms25ms1st
Unattributable311ms13ms0ms3rd
https://www.sanity.io/_next/static/chunks/167ci08t2mfto.js?dpl=dpl_7XhRSfxibpajdLWaTbdePehnDSnS303ms164ms26ms1st
https://cmp.osano.com/16CLWDTCcnYWI2HHP/e53d2bde-32d5-45a1-ab1a-16b98951bfe3/osano.js235ms200ms27ms3rd
https://www.googletagmanager.com/gtm.js?id=GTM-N3ZSHCP138ms99ms16ms3rd
https://www.googletagmanager.com/gtag/destination?id=AW-16634576538&cx=c&gtm=4e646072ms61ms10ms3rd
https://www.googletagmanager.com/gtag/js?id=G-K7J41TW619&cx=c&gtm=4e646065ms52ms11ms3rd
F
JS Bundles
Action
49 scripts, 919 KB unused
FIX
49 scripts, 919 KB unused
Warning::
https://www.sanity.io/_next/static/chunks/167ci08t...: 127 KB unused (44%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.sanity.io/_next/static/chunks/0sqt.ygt...: 123 KB unused (82%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.sanity.io/_next/static/chunks/12c3qy_6...: 97 KB unused (76%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.sanity.io/_next/static/chunks/0hmpifpn...: 80 KB unused (77%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtm.js?id=GTM-N3Z...: 77 KB unused (44%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 919 KB
919 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.sanity.io/_next/static/chunks/167ci08t2mfto.js?dpl=dpl_7XhRSfxibpajdLWaTbdePehnDSnS286 KB127 KB (44%)✓1st
https://www.sanity.io/_next/static/chunks/0sqt.ygt3kqko.js?dpl=dpl_7XhRSfxibpajdLWaTbdePehnDSnS150 KB123 KB (82%)✓1st
https://www.sanity.io/_next/static/chunks/12c3qy_6soa9g.js?dpl=dpl_7XhRSfxibpajdLWaTbdePehnDSnS132 KB97 KB (76%)✓1st
https://www.sanity.io/_next/static/chunks/0hmpifpnc3jey.js?dpl=dpl_7XhRSfxibpajdLWaTbdePehnDSnS108 KB80 KB (77%)✓1st
https://www.googletagmanager.com/gtm.js?id=GTM-N3ZSHCP175 KB77 KB (44%)✓3rd
https://www.googletagmanager.com/gtag/destination?id=AW-16634576538&cx=c&gtm=4e6460144 KB69 KB (48%)✓3rd
https://www.googletagmanager.com/gtag/js?id=G-K7J41TW619&cx=c&gtm=4e6460169 KB67 KB (40%)✓3rd
https://www.sanity.io/_next/static/chunks/0uz1gb6x4i~gy.js?dpl=dpl_7XhRSfxibpajdLWaTbdePehnDSnS145 KB46 KB (32%)✓1st
https://www.sanity.io/_next/static/chunks/0g5jmx.3u4xg2.js?dpl=dpl_7XhRSfxibpajdLWaTbdePehnDSnS42 KB41 KB (99%)✓1st
https://www.sanity.io/_next/static/chunks/0djohwm-41ade.js?dpl=dpl_7XhRSfxibpajdLWaTbdePehnDSnS88 KB38 KB (43%)✓1st

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

B
Image Optimization
35 images, 0 KB saveable
REVIEW
35 images, 0 KB saveable
Info::
All images are well-optimized
35 images 377 KB
0 oversized -0 KB
25 legacy format
0 missing dimensions CLS risk
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

B
HTTP Caching
public, max-age=0, must-revalidate
REVIEW
public, max-age=0, must-revalidate
Info::
Cache-Control header is set
Got: public, max-age=0, must-revalidate
Info::
ETag present — enables conditional (304) responses
Cache-Control

public, max-age=0, must-revalidate

DirectiveValueMeaning
public—Any cache may store this response
max-age0Cache for 0 seconds
must-revalidate—Must recheck with server after expiry
A+
Text Compression
All text resources are compressed
PASS
All text resources are compressed
Info::
All text resources are compressed
All text resources are properly compressed.
A+
Font Loading
7 fonts (177 KB)
PASS
7 fonts (177 KB)
Info::
7 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

7

177 KB total

Render-blocking

0

of 7

Dominant font-display

swap

Most common across fonts

Font loading timeline
Transfer FOIT (block) FOUT (swap)
0 ms 500 ms 1.0 s 1.5 s FCP 447 ms LCP 1.7 shttps://www.sanity.io/_next/static/media/ibm_plex_mono_bold_italic_subset-s.p.0w6iq6ec_1blj.woff2?dpl=dpl_7XhRSfxibpajdLWaTbdePehnDSnSibm_plex_mono_bold_ital... https://www.sanity.io/_next/static/media/ibm_plex_mono_bold_italic_subset-s.p.0w6iq6ec_1blj.woff2?dpl=dpl_7XhRSfxibpajdLWaTbdePehnDSnS — 12.9 KiB — 0 ms — font-display: swaphttps://www.sanity.io/_next/static/media/ibm_plex_mono_bold_subset-s.p.0o~xf2kclz5qt.woff2?dpl=dpl_7XhRSfxibpajdLWaTbdePehnDSnSibm_plex_mono_bold_subs... https://www.sanity.io/_next/static/media/ibm_plex_mono_bold_subset-s.p.0o~xf2kclz5qt.woff2?dpl=dpl_7XhRSfxibpajdLWaTbdePehnDSnS — 11.6 KiB — 0 ms — font-display: swaphttps://www.sanity.io/_next/static/media/ibm_plex_mono_regular_italic_subset-s.p.0l8emj58-vz5b.woff2?dpl=dpl_7XhRSfxibpajdLWaTbdePehnDSnSibm_plex_mono_regular_i... https://www.sanity.io/_next/static/media/ibm_plex_mono_regular_italic_subset-s.p.0l8emj58-vz5b.woff2?dpl=dpl_7XhRSfxibpajdLWaTbdePehnDSnS — 12.7 KiB — 0 ms — font-display: swaphttps://www.sanity.io/_next/static/media/ibm_plex_mono_regular_subset-s.p.0.9e4mj_ldshf.woff2?dpl=dpl_7XhRSfxibpajdLWaTbdePehnDSnSibm_plex_mono_regular_s... https://www.sanity.io/_next/static/media/ibm_plex_mono_regular_subset-s.p.0.9e4mj_ldshf.woff2?dpl=dpl_7XhRSfxibpajdLWaTbdePehnDSnS — 11.5 KiB — 0 ms — font-display: swaphttps://www.sanity.io/_next/static/media/waldenburg_fett-s.p.0h5moty~o0m8v.woff2?dpl=dpl_7XhRSfxibpajdLWaTbdePehnDSnSwaldenburg_fett-s.p.0h5... https://www.sanity.io/_next/static/media/waldenburg_fett-s.p.0h5moty~o0m8v.woff2?dpl=dpl_7XhRSfxibpajdLWaTbdePehnDSnS — 45.8 KiB — 0 ms — font-display: swaphttps://www.sanity.io/_next/static/media/waldenburg_normal-s.p.0tgxiqak_~9dn.woff2?dpl=dpl_7XhRSfxibpajdLWaTbdePehnDSnSwaldenburg_normal-s.p.0... https://www.sanity.io/_next/static/media/waldenburg_normal-s.p.0tgxiqak_~9dn.woff2?dpl=dpl_7XhRSfxibpajdLWaTbdePehnDSnS — 41.4 KiB — 0 ms — font-display: swaphttps://www.sanity.io/_next/static/media/waldenburg_normal_kursiv-s.p.140ht9l1oft.j.woff2?dpl=dpl_7XhRSfxibpajdLWaTbdePehnDSnSwaldenburg_normal_kursi... https://www.sanity.io/_next/static/media/waldenburg_normal_kursiv-s.p.140ht9l1oft.j.woff2?dpl=dpl_7XhRSfxibpajdLWaTbdePehnDSnS — 41.3 KiB — 0 ms — font-display: swap
ibm_plex_mono_bold_ital... woff2 swap
Size 13 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
ibm_plex_mono_bold_subs... woff2 swap
Size 12 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
ibm_plex_mono_regular_i... woff2 swap
Size 13 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
ibm_plex_mono_regular_s... woff2 swap
Size 11 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
waldenburg_fett-s.p.0h5... woff2 swap
Size 46 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
waldenburg_normal-s.p.0... woff2 swap
Size 41 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
waldenburg_normal_kursi... woff2 swap
Size 41 KB
Load time 0 ms
Start 0 ms
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
Info::
No caching issues found
All static resources have appropriate caching headers.
A+
Critical Rendering Path
No render-blocking resources
PASS
No render-blocking resources
Info::
No render-blocking resources detected
A+
Resource Hints
No optimization needed
PASS
No optimization needed
Info::
No resource hint issues
Network Waterfall
149 requests over 0ms
INFO

Performance analysis not available for this result.

Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
18% of JavaScript execution is third-party
First-party Third-party 821ms · 562KB · €9/mo
Unattributable
Other
Costly
Execution 311ms
Transfer 0 KB
Monthly Cost €3/mo
cmp.osano.com
Other
Costly
Execution 235ms
Transfer 75 KB
Unused 27%
Monthly Cost €3/mo
Google Tag Manager
Tag Manager
Optional
Execution 138ms
Transfer 175 KB
Unused 44%
Monthly Cost €2/mo
Google Tag Manager
Tag Manager
Optional
Execution 72ms
Transfer 144 KB
Unused 48%
Monthly Cost €1/mo
Google Tag Manager
Tag Manager
Optional
Execution 65ms
Transfer 169 KB
Unused 40%
Monthly Cost €1/mo

These scripts may cost more than they're worth

  • Unattributable adds 311ms and costs ~€3/month
  • cmp.osano.com adds 235ms and costs ~€3/month

Unattributable takes 311ms 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

cmp.osano.com takes 235ms 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

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.

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