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https://allbirds.com

Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
66
GRADE
D
FIX
5
REVIEW
1
PASS
6
INFO
2

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

Mobile Desktop
36
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.
96
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.

1.34 s

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

4.98 s

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

961 ms

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

0.010

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

4.73 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.

8.30 s

Page Load Progression

966 ms
1.9 s
2.9 s
3.9 s
4.8 s
5.8 s
6.8 s
7.7 s
Checks
14
6 PASS 1 REVIEW 5 FIX
F
Page Weight Budget
Action
8.6 MB transferred, 354 requests
FIX
8.6 MB transferred, 354 requests
Critical::
Page weighs 15.3 MB (8.6 MB transferred)
Warning::
Images are 4.2 MB — compress or use modern formats
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
Got: 4.2 MB
Warning::
JavaScript is 2.7 MB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 2.7 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::
354 HTTP requests — consider bundling or reducing
Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.
Info::
Estimated 1.8 g CO2 per page load
8.6 MB / 2.4 MB budget
8.6 MB transferred
354 requests
1.8 g CO2 per page load
Images 4.2 MiB 49%
JavaScript 2.7 MiB 32%
Other 1.0 MiB 12%
HTML 299.9 KiB 3%
Fonts 203.4 KiB 2%
Other 78.5 KiB 1%
Other 9.4 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 (8.6 MiB of 8.6 MiB)
Info::
Third-party blocking time is low (0 ms)
100%
First-party Third-party
F
JS Execution Cost
Action
6538ms total JS execution
FIX
6538ms total JS execution
Warning::
https://www.allbirds.com/cdn/shop/t/4054/assets/Sc...: 1078ms CPU time
Warning::
https://www.allbirds.com/: 870ms CPU time
Warning::
Unattributable: 829ms CPU time
Warning::
https://www.googletagmanager.com/gtm.js?id=GTM-TH8...: 385ms CPU time
Warning::
https://www.allbirds.com/cdn/shop/t/4054/assets/he...: 319ms CPU time
Warning::
Third-party scripts: 6538ms (100% of total)

Main Thread Breakdown

Script Evaluation 55% Other 22% Style & Layout 10% Script Parsing & Compilation 5% Rendering 3% Parse HTML & CSS 3%
ScriptTotalScriptingParse/CompileParty
https://www.allbirds.com/cdn/shop/t/4054/assets/ScrollTrigger.js1078ms272ms0ms3rd
https://www.allbirds.com/870ms84ms15ms3rd
Unattributable829ms61ms0ms3rd
https://www.googletagmanager.com/gtm.js?id=GTM-TH8KRSBJ385ms350ms29ms3rd
https://www.allbirds.com/cdn/shop/t/4054/assets/header.js319ms236ms0ms3rd
https://id-shop.govx.com/app/weareallbirds.myshopify.com/govx.js?shop=weareallbirds.myshopify.com296ms295ms1ms3rd
https://popupform.allbirds.com/w37htfhcq2/vendor/f0ff0959-79f9-4c1e-a197-0361a8f1cbb2/main.js?cb=82886068C4DADB1CB2033C792466D591246ms163ms25ms3rd
https://cdn.trackjs.com/agent/v3/latest/t.js241ms180ms2ms3rd
https://shopify-extension.getredo.com/998-62322427.js194ms178ms16ms3rd
https://www.allbirds.com/cdn/wpm/bcfa8229ew36b6053dp1e134caame9d83f21m.js178ms154ms9ms3rd

Showing top 10 of 29 scripts

F
JS Bundles
Action
202 scripts, 951 KB unused
FIX
202 scripts, 951 KB unused
Warning::
https://www.googletagmanager.com/gtm.js?id=GTM-TH8...: 73 KB unused (40%)
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?...: 67 KB unused (40%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://shopify-extension.getredo.com/9663-5e40532...: 67 KB unused (85%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://shopify-extension.getredo.com/998-62322427...: 67 KB unused (66%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 951 KB
951 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.googletagmanager.com/gtm.js?id=GTM-TH8KRSBJ181 KB73 KB (40%)✓3rd
https://popupform.allbirds.com/w37htfhcq2/vendor/f0ff0959-79f9-4c1e-a197-0361a8f1cbb2/main.js?cb=82886068C4DADB1CB2033C792466D591116 KB69 KB (59%)✓3rd
https://www.googletagmanager.com/gtag/destination?id=G-KB1068K0E6&cx=c&gtm=4e6411168 KB67 KB (40%)✓3rd
https://shopify-extension.getredo.com/9663-5e405327.js79 KB67 KB (85%)✓3rd
https://shopify-extension.getredo.com/998-62322427.js102 KB67 KB (66%)✓3rd
https://www.googletagmanager.com/gtag/js?id=AW-736740096&cx=c&gtm=4e6411143 KB64 KB (44%)✓3rd
https://www.googletagmanager.com/gtag/js?id=AW-786649265&cx=c&gtm=4e6411143 KB64 KB (44%)✓3rd
https://cdn.cookielaw.org/scripttemplates/202506.1.0/otBannerSdk.js120 KB63 KB (52%)✓3rd
https://www.googletagmanager.com/gtag/js?id=AW-935878905&cx=c&gtm=4e6411144 KB63 KB (43%)✓3rd
https://www.googletagmanager.com/gtm.js?id=GTM-WWZFMZRX154 KB61 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
57 images, 0 KB saveable
REVIEW
57 images, 0 KB saveable
Info::
All images are well-optimized
57 images 4.2 MB
0 oversized -0 KB
15 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 4.0 s 5.0 s FCP 1.3 s LCP 5.0 shttps://www.allbirds.com/cdn/shop/t/4054/assets/geograph-regular.woff2geograph-regular.woff2 https://www.allbirds.com/cdn/shop/t/4054/assets/geograph-regular.woff2 — 34.3 KiB — 0 ms — font-display: swaphttps://www.allbirds.com/cdn/shop/t/4054/assets/geograph-medium.woff2geograph-medium.woff2 https://www.allbirds.com/cdn/shop/t/4054/assets/geograph-medium.woff2 — 34.9 KiB — 0 ms — font-display: swaphttps://www.allbirds.com/cdn/shop/t/4054/assets/self-modern_regular_web.woff2self-modern_regular_web... https://www.allbirds.com/cdn/shop/t/4054/assets/self-modern_regular_web.woff2 — 24.6 KiB — 0 ms — font-display: swaphttps://www.allbirds.com/cdn/shop/t/4054/assets/akkurat-mono.woff2akkurat-mono.woff2 https://www.allbirds.com/cdn/shop/t/4054/assets/akkurat-mono.woff2 — 10.9 KiB — 0 ms — font-display: swaphttps://www.allbirds.com/cdn/shop/t/4054/assets/geograph-bold.woff2geograph-bold.woff2 https://www.allbirds.com/cdn/shop/t/4054/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
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
akkurat-mono.woff2 woff2 swap
Size 11 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
354 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 6538ms · 1912KB · $37/mo
www.allbirds.com
Other
Costly
Execution 1078ms
Transfer 65 KB
Unused 36%
Monthly Cost $6/mo
www.allbirds.com
Other
Costly
Execution 870ms
Transfer 109 KB
Monthly Cost $5/mo
Unattributable
Other
Costly
Execution 829ms
Transfer 0 KB
Monthly Cost $5/mo
Google Tag Manager
Tag Manager
Costly
Execution 385ms
Transfer 181 KB
Unused 40%
Monthly Cost $2/mo
www.allbirds.com
Other
Costly
Execution 319ms
Transfer 7 KB
Monthly Cost $2/mo
id-shop.govx.com
Other
Costly
Execution 296ms
Transfer 7 KB
Monthly Cost $2/mo
popupform.allbirds.com
Other
Costly
Execution 246ms
Transfer 116 KB
Unused 59%
Monthly Cost $1/mo
cdn.trackjs.com
Other
Costly
Execution 241ms
Transfer 11 KB
Monthly Cost $1/mo
shopify-extension.getredo.com
Other
Optional
Execution 194ms
Transfer 102 KB
Unused 66%
Monthly Cost $1/mo
www.allbirds.com
Other
Optional
Execution 178ms
Transfer 58 KB
Unused 44%
Monthly Cost $1/mo
shopify-extension.getredo.com
Other
Optional
Execution 154ms
Transfer 107 KB
Unused 55%
Monthly Cost $1/mo
cdn.gladly.com
Other
Optional
Execution 143ms
Transfer 43 KB
Monthly Cost $1/mo
Google Tag Manager
Tag Manager
Optional
Execution 133ms
Transfer 144 KB
Unused 43%
Monthly Cost $1/mo
shopify-extension.getredo.com
Other
Optional
Execution 127ms
Transfer 43 KB
Unused 64%
Monthly Cost $1/mo
OneTrust
Consent
Essential
Execution 124ms
Transfer 120 KB
Unused 52%
Monthly Cost $1/mo
Google Tag Manager
Tag Manager
Optional
Execution 110ms
Transfer 143 KB
Unused 44%
Monthly Cost $1/mo
Google Tag Manager
Tag Manager
Optional
Execution 105ms
Transfer 143 KB
Unused 44%
Monthly Cost $1/mo
Google Tag Manager
Tag Manager
Optional
Execution 102ms
Transfer 154 KB
Unused 40%
Monthly Cost $1/mo
Google Tag Manager
Tag Manager
Optional
Execution 102ms
Transfer 168 KB
Unused 40%
Monthly Cost $1/mo
Amplitude
Analytics
Optional
Execution 93ms
Transfer 43 KB
Monthly Cost $1/mo
jssdk.allbirds.com
Other
Optional
Execution 92ms
Transfer 31 KB
Monthly Cost $1/mo
www.allbirds.com
Other
Optional
Execution 90ms
Transfer 2 KB
Monthly Cost $1/mo
www.allbirds.com
Other
Optional
Execution 86ms
Transfer 2 KB
Monthly Cost $0/mo
beacon.riskified.com
Other
Optional
Execution 85ms
Transfer 17 KB
Monthly Cost $0/mo
www.allbirds.com
Other
Optional
Execution 84ms
Transfer 2 KB
Monthly Cost $0/mo
shopify-extension.getredo.com
Other
Optional
Execution 82ms
Transfer 49 KB
Unused 71%
Monthly Cost $0/mo
www.allbirds.com
Other
Optional
Execution 71ms
Transfer 2 KB
Monthly Cost $0/mo
www.allbirds.com
Other
Optional
Execution 62ms
Transfer 21 KB
Monthly Cost $0/mo
www.allbirds.com
Other
Optional
Execution 55ms
Transfer 21 KB
Monthly Cost $0/mo

These scripts may cost more than they're worth

  • www.allbirds.com adds 1078ms and costs ~$6/month
  • www.allbirds.com adds 870ms and costs ~$5/month
  • Unattributable adds 829ms and costs ~$5/month
  • Google Tag Manager adds 385ms and costs ~$2/month
  • www.allbirds.com adds 319ms and costs ~$2/month
  • id-shop.govx.com adds 296ms and costs ~$2/month
  • popupform.allbirds.com adds 246ms and costs ~$1/month
  • cdn.trackjs.com adds 241ms and costs ~$1/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

www.allbirds.com takes 1078ms 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 870ms 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

Unattributable takes 829ms 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 385ms 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 319ms 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

id-shop.govx.com takes 296ms 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

popupform.allbirds.com takes 246ms 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

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

cdn.trackjs.com takes 241ms 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

66% 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

55% 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

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

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

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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