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https://allbirds.com

Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
72
GRADE
C
FIX
5
REVIEW
1
PASS
6
INFO
2

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

Mobile Desktop
41
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
100
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
77
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
92
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.

1.30 s

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

3.61 s

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

766 ms

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

0.003

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

5.02 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.

8.48 s

Page Load Progression

1.1 s
2.2 s
3.4 s
4.5 s
5.6 s
6.7 s
7.8 s
8.9 s
Checks
14
6 PASS 1 REVIEW 5 FIX
F
Page Weight Budget
Action
13.9 MB transferred, 369 requests
FIX
13.9 MB transferred, 369 requests
Critical::
Page weighs 20.8 MB (13.9 MB transferred)
Warning::
Images are 4.6 MB — compress or use modern formats
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
Got: 4.6 MB
Warning::
JavaScript is 2.8 MB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 2.8 MB
Info::
Fonts are 203 KB — consider subsetting or using system fonts
Subset fonts to include only used characters, or switch to system font stacks.
Got: 203 KB
Warning::
369 HTTP requests — consider bundling or reducing
Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.
Info::
Estimated 2.9 g CO2 per page load
13.9 MB / 2.4 MB budget
13.9 MB transferred
369 requests
2.9 g CO2 per page load
Other 5.0 MiB 36%
Images 4.6 MiB 33%
JavaScript 2.8 MiB 20%
Other 1021.1 KiB 7%
HTML 300.6 KiB 2%
Fonts 203.4 KiB 1%
Other 77.3 KiB 1%
Other 9.6 KiB 0%
CSS 8.7 KiB 0%
Other 7.6 KiB 0%
Other 0 B 0%
0 2.4 MB 4.9 MB
Over budget

Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.

Why this matters

Image bandwidth is high — modern formats (WebP/AVIF) and resizing typically cut it 50%+.

Source: web.dev

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

Subset fonts to include only used characters, or switch to system font stacks.

Why this matters

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.

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
100% third-party, 0 ms blocking
FIX
100% third-party, 0 ms blocking
Warning::
Third-party code accounts for 100% of page weight (13.9 MiB of 13.9 MiB)
Info::
Third-party blocking time is low (0 ms)
100%
First-party Third-party
F
JS Execution Cost
Action
5168ms total JS execution
FIX
5168ms total JS execution
Warning::
Unattributable: 941ms CPU time
Warning::
https://www.allbirds.com/cdn/shop/t/4071/assets/Sc...: 599ms CPU time
Warning::
https://www.allbirds.com/: 587ms CPU time
Warning::
https://www.googletagmanager.com/gtm.js?id=GTM-TH8...: 306ms CPU time
Warning::
https://www.allbirds.com/cdn/shop/t/4071/assets/he...: 282ms CPU time
Warning::
Third-party scripts: 5168ms (100% of total)

Main Thread Breakdown

Script Evaluation 56% Other 22% Style & Layout 9% Script Parsing & Compilation 6% Parse HTML & CSS 4%
ScriptTotalScriptingParse/CompileParty
Unattributable941ms63ms0ms3rd
https://www.allbirds.com/cdn/shop/t/4071/assets/ScrollTrigger.js599ms261ms1ms3rd
https://www.allbirds.com/587ms58ms11ms3rd
https://www.googletagmanager.com/gtm.js?id=GTM-TH8KRSBJ306ms267ms33ms3rd
https://www.allbirds.com/cdn/shop/t/4071/assets/header.js282ms216ms0ms3rd
https://shopify-extension.getredo.com/998-928ba8fc.js191ms176ms14ms3rd
https://shopify-extension.getredo.com/main.js?widget_id=l3cmm7m70dmwcb2&shop=weareallbirds.myshopify.com145ms129ms14ms3rd
https://cdn.cookielaw.org/scripttemplates/202506.1.0/otBannerSdk.js126ms89ms19ms3rd
https://shopify-extension.getredo.com/5987-c5de408a.js124ms119ms5ms3rd
https://www.allbirds.com/cdn/wpm/b0e8c7c7aw41bd75a1p837d7fd4m8b145375m.js123ms110ms7ms3rd

Showing top 10 of 30 scripts

F
JS Bundles
Action
202 scripts, 957 KB unused
FIX
202 scripts, 957 KB unused
Warning::
https://www.googletagmanager.com/gtm.js?id=GTM-TH8...: 74 KB unused (41%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://popupform.allbirds.com/w37htfhcq2/vendor/f...: 69 KB unused (59%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtag/destination?...: 68 KB unused (40%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://shopify-extension.getredo.com/9663-21477b0...: 67 KB unused (85%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://shopify-extension.getredo.com/998-928ba8fc...: 66 KB unused (63%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 957 KB
957 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.googletagmanager.com/gtm.js?id=GTM-TH8KRSBJ182 KB74 KB (41%)✓3rd
https://popupform.allbirds.com/w37htfhcq2/vendor/f0ff0959-79f9-4c1e-a197-0361a8f1cbb2/main.js?cb=0036016EDAA80E99066F39CFE5BC2BF2116 KB69 KB (59%)✓3rd
https://www.googletagmanager.com/gtag/destination?id=G-KB1068K0E6&cx=c&gtm=4e6461169 KB68 KB (40%)✓3rd
https://shopify-extension.getredo.com/9663-21477b0f.js79 KB67 KB (85%)✓3rd
https://shopify-extension.getredo.com/998-928ba8fc.js105 KB66 KB (63%)✓3rd
https://www.googletagmanager.com/gtag/js?id=AW-736740096&cx=c&gtm=4e6461144 KB64 KB (45%)✓3rd
https://www.googletagmanager.com/gtag/js?id=AW-786649265&cx=c&gtm=4e6461144 KB64 KB (45%)✓3rd
https://www.googletagmanager.com/gtag/js?id=AW-935878905&cx=c&gtm=4e6461h1145 KB64 KB (44%)✓3rd
https://cdn.cookielaw.org/scripttemplates/202506.1.0/otBannerSdk.js120 KB63 KB (52%)✓3rd
https://www.googletagmanager.com/gtm.js?id=GTM-WWZFMZRX155 KB62 KB (40%)✓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

D
HTTP Caching
Action
no-store (uncacheable)
FIX
no-store (uncacheable)
Info::
Cache-Control: no-store prevents all caching
Intentional for dynamic content, but increases server load for every page view.
Got: private, no-store
Info::
No ETag or Last-Modified header
Conditional requests (304 Not Modified) are not possible without validators.
Cache-Control

private, no-store

DirectiveValueMeaning
private—Only browser cache, not CDN/proxy
no-store—Never cache this response
B
Image Optimization
71 images, 0 KB saveable
REVIEW
71 images, 0 KB saveable
Info::
All images are well-optimized
71 images 4.6 MB
0 oversized -0 KB
13 legacy format
0 missing dimensions CLS risk
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
8 fonts (273 KB)
PASS
8 fonts (273 KB)
Info::
8 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

8

273 KB total

Render-blocking

0

of 8

Dominant font-display

swap

Most common across fonts

Font loading timeline
Transfer FOIT (block) FOUT (swap)
0 ms 1.0 s 2.0 s 3.0 s FCP 1.3 s LCP 3.6 shttps://www.allbirds.com/cdn/shop/t/4071/assets/geograph-regular.woff2geograph-regular.woff2 https://www.allbirds.com/cdn/shop/t/4071/assets/geograph-regular.woff2 — 34.3 KiB — 0 ms — font-display: swaphttps://www.allbirds.com/cdn/shop/t/4071/assets/geograph-medium.woff2geograph-medium.woff2 https://www.allbirds.com/cdn/shop/t/4071/assets/geograph-medium.woff2 — 34.9 KiB — 0 ms — font-display: swaphttps://www.allbirds.com/cdn/shop/t/4071/assets/akkurat-mono.woff2akkurat-mono.woff2 https://www.allbirds.com/cdn/shop/t/4071/assets/akkurat-mono.woff2 — 10.9 KiB — 0 ms — font-display: swaphttps://www.allbirds.com/cdn/shop/t/4071/assets/self-modern_regular_web.woff2self-modern_regular_web... https://www.allbirds.com/cdn/shop/t/4071/assets/self-modern_regular_web.woff2 — 24.6 KiB — 0 ms — font-display: swaphttps://www.allbirds.com/cdn/shop/t/4071/assets/geograph-bold.woff2geograph-bold.woff2 https://www.allbirds.com/cdn/shop/t/4071/assets/geograph-bold.woff2 — 35.4 KiB — 0 ms — font-display: swaphttps://cdn.shopify.com/shop-assets/static_uploads/shoplift/GTStandard-MRegular.woff2GTStandard-MRegular.woff2 https://cdn.shopify.com/shop-assets/static_uploads/shoplift/GTStandard-MRegular.woff2 — 63.2 KiB — 0 ms — font-display: swaphttps://cdn.shopify.com/s/files/1/1104/4168/files/geograph-regular_8e9ffb2c-0e1f-4f0c-96be-aad7e378d3b3.woff2?v=1719584207geograph-regular_8e9ffb... https://cdn.shopify.com/s/files/1/1104/4168/files/geograph-regular_8e9ffb2c-0e1f-4f0c-96be-aad7e378d3b3.woff2?v=1719584207 — 34.3 KiB — 0 ms — font-display: swaphttps://cdn.shopify.com/s/files/1/1104/4168/files/geograph-bold_769abb60-0752-447c-9785-bbbafeaf12c6.woff2?v=1719584207geograph-bold_769abb60-... https://cdn.shopify.com/s/files/1/1104/4168/files/geograph-bold_769abb60-0752-447c-9785-bbbafeaf12c6.woff2?v=1719584207 — 35.2 KiB — 0 ms — font-display: swap
geograph-regular.woff2 woff2 swap
Size 34 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
geograph-medium.woff2 woff2 swap
Size 35 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
akkurat-mono.woff2 woff2 swap
Size 11 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
self-modern_regular_web... woff2 swap
Size 25 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
geograph-bold.woff2 woff2 swap
Size 35 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
GTStandard-MRegular.woff2 woff2 swap
Size 63 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
geograph-regular_8e9ffb... woff2 swap
Size 34 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
geograph-bold_769abb60-... woff2 swap
Size 35 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
A+
Green Hosting
Whether the site is served from green-energy infrastructure
PASS

Green Hosting

This site is hosted on green energy infrastructure

Provider: Cloudflare

Network Waterfall
369 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
100% of JavaScript execution is third-party
First-party Third-party 5168ms · 1944KB · $30/mo
Unattributable
Other
Costly
Execution 941ms
Transfer 0 KB
Monthly Cost $5/mo
www.allbirds.com
Other
Costly
Execution 599ms
Transfer 65 KB
Unused 36%
Monthly Cost $3/mo
www.allbirds.com
Other
Costly
Execution 587ms
Transfer 109 KB
Monthly Cost $3/mo
Google Tag Manager
Tag Manager
Costly
Execution 306ms
Transfer 182 KB
Unused 41%
Monthly Cost $2/mo
www.allbirds.com
Other
Costly
Execution 282ms
Transfer 7 KB
Monthly Cost $2/mo
shopify-extension.getredo.com
Other
Optional
Execution 191ms
Transfer 105 KB
Unused 63%
Monthly Cost $1/mo
shopify-extension.getredo.com
Other
Optional
Execution 145ms
Transfer 107 KB
Unused 54%
Monthly Cost $1/mo
OneTrust
Consent
Essential
Execution 126ms
Transfer 120 KB
Unused 52%
Monthly Cost $1/mo
shopify-extension.getredo.com
Other
Optional
Execution 124ms
Transfer 43 KB
Unused 64%
Monthly Cost $1/mo
www.allbirds.com
Other
Optional
Execution 123ms
Transfer 61 KB
Unused 45%
Monthly Cost $1/mo
Google Tag Manager
Tag Manager
Optional
Execution 119ms
Transfer 169 KB
Unused 40%
Monthly Cost $1/mo
Google Tag Manager
Tag Manager
Optional
Execution 117ms
Transfer 144 KB
Unused 45%
Monthly Cost $1/mo
beacon.riskified.com
Other
Optional
Execution 114ms
Transfer 17 KB
Monthly Cost $1/mo
Google Tag Manager
Tag Manager
Optional
Execution 113ms
Transfer 145 KB
Unused 44%
Monthly Cost $1/mo
www.allbirds.com
Other
Optional
Execution 109ms
Transfer 2 KB
Monthly Cost $1/mo
popupform.allbirds.com
Other
Optional
Execution 107ms
Transfer 116 KB
Unused 59%
Monthly Cost $1/mo
popupform.allbirds.com
Other
Optional
Execution 104ms
Transfer 1 KB
Monthly Cost $1/mo
Google Tag Manager
Tag Manager
Optional
Execution 101ms
Transfer 155 KB
Unused 40%
Monthly Cost $1/mo
cdn.trackjs.com
Other
Optional
Execution 98ms
Transfer 11 KB
Monthly Cost $1/mo
Google Tag Manager
Tag Manager
Optional
Execution 95ms
Transfer 144 KB
Unused 45%
Monthly Cost $1/mo
cdn.gladly.com
Other
Optional
Execution 82ms
Transfer 43 KB
Monthly Cost $0/mo
Amplitude
Analytics
Optional
Execution 82ms
Transfer 44 KB
Monthly Cost $0/mo
shopify-extension.getredo.com
Other
Optional
Execution 81ms
Transfer 49 KB
Unused 71%
Monthly Cost $0/mo
www.allbirds.com
Other
Optional
Execution 74ms
Transfer 2 KB
Monthly Cost $0/mo
www.allbirds.com
Other
Optional
Execution 66ms
Transfer 3 KB
Monthly Cost $0/mo
www.allbirds.com
Other
Optional
Execution 64ms
Transfer 2 KB
Monthly Cost $0/mo
www.allbirds.com
Other
Optional
Execution 62ms
Transfer 28 KB
Monthly Cost $0/mo
cdn.gladly.com
Other
Optional
Execution 57ms
Transfer 47 KB
Unused 47%
Monthly Cost $0/mo
www.allbirds.com
Other
Optional
Execution 51ms
Transfer 2 KB
Monthly Cost $0/mo
www.allbirds.com
Other
Optional
Execution 50ms
Transfer 21 KB
Monthly Cost $0/mo

These scripts may cost more than they're worth

  • Unattributable adds 941ms and costs ~$5/month
  • www.allbirds.com adds 599ms and costs ~$3/month
  • www.allbirds.com adds 587ms and costs ~$3/month
  • Google Tag Manager adds 306ms and costs ~$2/month
  • www.allbirds.com adds 282ms and costs ~$2/month

100% 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

Unattributable takes 941ms 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

www.allbirds.com takes 599ms 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

www.allbirds.com takes 587ms 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

Google Tag Manager takes 306ms 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

www.allbirds.com takes 282ms 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

63% of shopify-extension.getredo.com'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

54% of shopify-extension.getredo.com'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

52% of OneTrust'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

64% of shopify-extension.getredo.com'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

59% of popupform.allbirds.com'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

71% of shopify-extension.getredo.com'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.

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