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https://www.iterm2.com

Performance

· 13 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
94
GRADE
A
FIX
2
REVIEW
1
PASS
9
INFO
1

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

Mobile Desktop
98
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
63
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.
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.

805 ms

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

1.08 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.

0.008

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

805 ms

Time to Interactive Time to Interactive — how long until the page is fully interactive and responds to user input. Under 3.8s is good.

1.08 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
13
9 PASS 1 REVIEW 2 FIX
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 (139.7 KiB of 140.3 KiB)
Info::
Third-party blocking time is low (0 ms)
100%
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.

B
Image Optimization
3 images, 0 KB saveable
REVIEW
3 images, 0 KB saveable
Warning::
https://iterm2.com/img/download-button.png is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
3 images 82 KB
0 oversized -0 KB
3 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+
Page Weight Budget
140 KB transferred, 10 requests
PASS
140 KB transferred, 10 requests
Info::
Page weighs 262 KB (140 KB transferred)
Info::
10 HTTP requests
Info::
Estimated 0.03 g CO2 per page load
140 KB / 2.4 MB budget
140 KB transferred
10 requests
0.03 g CO2 per page load
Images 81.8 KiB 58%
JavaScript 44.6 KiB 32%
CSS 7.6 KiB 5%
Other 3.4 KiB 2%
HTML 2.5 KiB 2%
Other 452 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+
JS Execution Cost
No JS execution data
PASS
No JS execution data
Info::
No significant JS execution detected

Main Thread Breakdown

Script Evaluation 38% Other 33% Style & Layout 18% Script Parsing & Compilation 5% Parse HTML & CSS 3%
A+
Font Loading
No web fonts (system fonts)
PASS
No web fonts (system fonts)
Info::
No web fonts loaded — system fonts are fastest
No web fonts loaded — system fonts are optimal.
A+
JS Bundles
2 scripts, 0 KB unused
PASS
2 scripts, 0 KB unused
0 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://iterm2.com/js/scripts.js34 KB—✓3rd
https://static.cloudflareinsights.com/beacon.min.js/v8c78df7c7c0f484497ecbca7046644da177152312451611 KB—✓3rd
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
10 requests over 0ms
INFO

Performance analysis not available for this result.

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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