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https://grubhub.com

Performance

· 15 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
93
GRADE
A
FIX
2
REVIEW
1
PASS
10
INFO
2

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

Mobile Desktop
81
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
58
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
73
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
83
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.

3.56 s

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

3.80 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.

0.000

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

3.56 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.

3.80 s

Page Load Progression

375 ms
750 ms
1.1 s
1.5 s
1.9 s
2.2 s
2.6 s
3.0 s
Checks
15
10 PASS 1 REVIEW 2 FIX
D
Third-Party Impact
Action
98% third-party, 0 ms blocking
FIX
98% third-party, 0 ms blocking
Warning::
Third-party code accounts for 98% of page weight (191.2 KiB of 194.2 KiB)
Info::
Third-party blocking time is low (0 ms)
98%
First-party Third-party
F
HTTP Caching
Action
No cache headers
FIX
No cache headers
Warning::
No Cache-Control header found
Browsers will use heuristic caching, which can be unpredictable. Set explicit cache headers.

No Cache-Control header

Adding a Cache-Control header can significantly improve repeat-visit performance.

C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A+
Page Weight Budget
194 KB transferred, 9 requests
PASS
194 KB transferred, 9 requests
Info::
Page weighs 292 KB (194 KB transferred)
Info::
9 HTTP requests
Info::
Estimated 0.04 g CO2 per page load
194 KB / 2.4 MB budget
194 KB transferred
9 requests
0.04 g CO2 per page load
Fonts 159.3 KiB 82%
CSS 30.2 KiB 16%
HTML 3.0 KiB 2%
Images 1.8 KiB 1%
Other 0 B 0%
0 2.4 MB 4.9 MB
Under budget
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
Image Optimization
2 images, 0 KB saveable
PASS
2 images, 0 KB saveable
Warning::
https://gh-prod-umami-grubhub.s3-website-us-east-1... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
2 images 2 KB
0 oversized -0 KB
1 legacy format
1 missing dimensions CLS risk

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

A+
JS Execution Cost
89ms total JS execution
PASS
89ms total JS execution
Info::
Unattributable: 89ms CPU time
Warning::
Third-party scripts: 89ms (100% of total)

Main Thread Breakdown

Other 65% Style & Layout 21% Script Evaluation 9% Parse HTML & CSS 3%
ScriptTotalScriptingParse/CompileParty
Unattributable89ms6ms0ms3rd
A+
Font Loading
3 fonts (159 KB)
PASS
3 fonts (159 KB)
Info::
3 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

3

159 KB total

Render-blocking

0

of 3

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 3.6 s LCP 3.8 shttps://assets.grubhub.com/libs/cookbook-web-fonts/v1.0.12/bagoss-standard/BagossStandard-Medium.otfBagossStandard-Medium.otf https://assets.grubhub.com/libs/cookbook-web-fonts/v1.0.12/bagoss-standard/BagossStandard-Medium.otf — 58.8 KiB — 89 ms — font-display: swaphttps://assets.grubhub.com/libs/cookbook-web-fonts/v1.0.12/bagoss-standard/BagossStandard-Regular.otfBagossStandard-Regular.otf https://assets.grubhub.com/libs/cookbook-web-fonts/v1.0.12/bagoss-standard/BagossStandard-Regular.otf — 58.6 KiB — 89 ms — font-display: swaphttps://assets.grubhub.com/libs/mochi/2.0.433/graphik-regular/graphik-regular.woffgraphik-regular.woff https://assets.grubhub.com/libs/mochi/2.0.433/graphik-regular/graphik-regular.woff — 41.8 KiB — 191 ms — font-display: swap
BagossStandard-Medium.otf otf swap
Size 59 KB
Load time 89 ms
Start 946 ms
Risk FOUT — text flashes from fallback to web font
  • Convert to woff2 for ~30% smaller file size
BagossStandard-Regular.otf otf swap
Size 59 KB
Load time 89 ms
Start 946 ms
Risk FOUT — text flashes from fallback to web font
  • Convert to woff2 for ~30% smaller file size
graphik-regular.woff woff swap
Size 42 KB
Load time 191 ms
Start 946 ms
Risk FOUT — text flashes from fallback to web font
  • 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)

Fixing the unchecked items could save ~48 KB and ~96 ms

A+
JS Bundles
No JavaScript
PASS
No JavaScript
Info::
No JavaScript bundles
No JavaScript files loaded.
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
Page Weight Inventory
9 resources · 194 KB · 0 KB savings available
PASS
9 resources · 194 KB · 0 KB savings available
Info::
Within 1MB page-weight target
Got: 194 KB
Warning::
8 third-party resources (98% of weight)
9 resources · 194.2 KiB · 8 third-party Within 1MB page-weight target
Font 82% · 159.3 KiB
CSS 16% · 30.2 KiB
Document 2% · 3.0 KiB
Image 1% · 1.8 KiB
Other 0% · 0 B
Network Waterfall
9 requests over 1138ms
INFO
0 ms 1.0 s 2.0 s 3.0 s FCP 3.6 s LCP 3.8 shttps://grubhub.com// https://grubhub.com/ — 200 — 3.0 KiB — 47 ms — h2https://gh-prod-umami-grubhub.s3-website-us-east-1.amazonaws.com/img/grubhub-error-image.svggh-prod-umami-grubhub.s3-website-us... https://gh-prod-umami-grubhub.s3-website-us-east-1.amazonaws.com/img/grubhub-error-image.svg — -1 — 0 B — 883 ms — https://res.cloudinary.com/grubhub-assets/image/upload/v1651068764/Citrus-assets/Logos/No%20Registered%20Mark/1_Grubhub_Logo_NotRegistered/SVG/grubhub_NotRegistered_Orange_RGB.svgres.cloudinary.com/grubhub-assets/i... https://res.cloudinary.com/grubhub-assets/image/upload/v1651068764/Citrus-assets/Logos/No%20Registered%20Mark/1_Grubhub_Logo_NotRegistered/SVG/grubhub_NotRegistered_Orange_RGB.svg — 200 — 1.8 KiB — 147 ms — h2https://gh-prod-umami-grubhub.s3.us-east-1.amazonaws.com/css/grubhub-out-of-country.cssgh-prod-umami-grubhub.s3.us-east-1.... https://gh-prod-umami-grubhub.s3.us-east-1.amazonaws.com/css/grubhub-out-of-country.css — 200 — 30.2 KiB — 482 ms — http/1.1https://assets.grubhub.com/libs/cookbook-web-fonts/v1.0.12/bagoss-standard/BagossStandard-Medium.otfassets.grubhub.com/libs/cookbook-we... https://assets.grubhub.com/libs/cookbook-web-fonts/v1.0.12/bagoss-standard/BagossStandard-Medium.otf — 200 — 58.8 KiB — 89 ms — h2https://assets.grubhub.com/libs/cookbook-web-fonts/v1.0.12/bagoss-standard/BagossStandard-Regular.otfassets.grubhub.com/libs/cookbook-we... https://assets.grubhub.com/libs/cookbook-web-fonts/v1.0.12/bagoss-standard/BagossStandard-Regular.otf — 200 — 58.6 KiB — 89 ms — h2https://assets.grubhub.com/libs/mochi/2.0.433/graphik-regular/graphik-regular.woffassets.grubhub.com/libs/mochi/2.0.4... https://assets.grubhub.com/libs/mochi/2.0.433/graphik-regular/graphik-regular.woff — 200 — 41.8 KiB — 191 ms — h2http://gh-prod-umami-grubhub.s3-website-us-east-1.amazonaws.com/href/grubhub/favicon.icogh-prod-umami-grubhub.s3-website-us... http://gh-prod-umami-grubhub.s3-website-us-east-1.amazonaws.com/href/grubhub/favicon.ico — -1 — 0 B — 0 ms — http://gh-prod-umami-grubhub.s3-website-us-east-1.amazonaws.com/img/grubhub/favicon.icogh-prod-umami-grubhub.s3-website-us... http://gh-prod-umami-grubhub.s3-website-us-east-1.amazonaws.com/img/grubhub/favicon.ico — -1 — 0 B — 0 ms —
HTML JavaScript CSS Images Fonts XHR/Fetch Other
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 89ms · 0KB · $1/mo
Unattributable
Other
Optional
Execution 89ms
Transfer 0 KB
Monthly Cost $1/mo

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

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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