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https://zenwriting.net

Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
92
GRADE
A
FIX
2
REVIEW
1
PASS
10
INFO
1

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

Mobile Desktop
99
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
97
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.

669 ms

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

974 ms

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.

669 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.

974 ms

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
14
10 PASS 1 REVIEW 2 FIX
D
Third-Party Impact
Action
64% third-party, 0 ms blocking
FIX
64% third-party, 0 ms blocking
Warning::
Third-party code accounts for 64% of page weight (81.3 KiB of 127.0 KiB)
Info::
Third-party blocking time is low (0 ms)
36%
64%
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
Image Optimization
Action
4 images, 0 KB saveable
REVIEW
4 images, 0 KB saveable
Warning::
https://zenwriting.net/features/noun_branding_1885... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://zenwriting.net/features/noun_The%20Process... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://zenwriting.net/features/noun_3d%20modeling... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
4 images 17 KB
0 oversized -0 KB
4 legacy format
3 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

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

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
127 KB transferred, 12 requests
PASS
127 KB transferred, 12 requests
Info::
Page weighs 267 KB (127 KB transferred)
Info::
12 HTTP requests
Info::
Estimated 0.03 g CO2 per page load
127 KB / 2.4 MB budget
127 KB transferred
12 requests
0.03 g CO2 per page load
Fonts 78.9 KiB 62%
CSS 18.2 KiB 14%
Images 17.0 KiB 13%
Other 8.6 KiB 7%
HTML 2.6 KiB 2%
JavaScript 1.7 KiB 1%
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

Other 49% Style & Layout 36% Script Evaluation 5% Parse HTML & CSS 5% Rendering 4%
A+
Font Loading
2 fonts (79 KB)
PASS
2 fonts (79 KB)
Info::
2 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

2

79 KB total

Render-blocking

0

of 2

Dominant font-display

swap

Most common across fonts

Font loading timeline
Transfer FOIT (block) FOUT (swap)
0 ms 500 ms 1.0 s FCP 669 ms LCP 974 mshttps://fonts.gstatic.com/s/lora/v37/0QIvMX1D_JOuMwr7I_FMl_E.woff20QIvMX1D_JOuMwr7I_FMl_E... https://fonts.gstatic.com/s/lora/v37/0QIvMX1D_JOuMwr7I_FMl_E.woff2 — 36.9 KiB — 56 ms — font-display: swaphttps://fonts.gstatic.com/s/opensans/v44/memvYaGs126MiZpBA-UvWbX2vVnXBbObj2OVTS-mu0SC55I.woff2memvYaGs126MiZpBA-UvWbX... https://fonts.gstatic.com/s/opensans/v44/memvYaGs126MiZpBA-UvWbX2vVnXBbObj2OVTS-mu0SC55I.woff2 — 42.0 KiB — 60 ms — font-display: swap
0QIvMX1D_JOuMwr7I_FMl_E... woff2 swap
Size 37 KB
Load time 56 ms
Start 254 ms
Risk FOUT — text flashes from fallback to web font
memvYaGs126MiZpBA-UvWbX... woff2 swap
Size 42 KB
Load time 60 ms
Start 254 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+
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://zenwriting.net/cdn-cgi/scripts/5c5dd728/cloudflare-static/email-decode.min.js1 KB—✓1st
https://zenwriting.net/js/scripts.min.bf1e1f7ae8e03db5f012356e825843facdff51c0a559cb0d27fe2bbe1db405c2.js1 KB—✓1st
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
12 resources · 127 KB · 0 KB savings available
PASS
12 resources · 127 KB · 0 KB savings available
Info::
Within 1MB page-weight target
Got: 127 KB
Warning::
3 third-party resources (64% of weight)
12 resources · 127.0 KiB · 3 third-party Within 1MB page-weight target
Font 62% · 78.9 KiB
Image 20% · 25.6 KiB
CSS 14% · 18.2 KiB
Document 2% · 2.6 KiB
JavaScript 1% · 1.7 KiB
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
12 requests over 349ms
INFO
0 ms 500 ms 1.0 s FCP 669 ms LCP 974 mshttps://zenwriting.net// https://zenwriting.net/ — 200 — 2.6 KiB — 81 ms — h3https://zenwriting.net/css/style.min.3e25e0d8b6702e00684d9a35cfc1f3461ff28f5139aa60ece211c234673b3fdd.css/css/style.min.3e25e0d8b6702e00684d... https://zenwriting.net/css/style.min.3e25e0d8b6702e00684d9a35cfc1f3461ff28f5139aa60ece211c234673b3fdd.css — 200 — 15.8 KiB — 55 ms — h3https://zenwriting.net/features/noun_branding_1885335.svg/features/noun_branding_1885335.svg https://zenwriting.net/features/noun_branding_1885335.svg — 200 — 1.8 KiB — 28 ms — h3https://zenwriting.net/features/noun_The%20Process_1885341.svg/features/noun_The%20Process_188534... https://zenwriting.net/features/noun_The%20Process_1885341.svg — 200 — 1.9 KiB — 53 ms — h3https://zenwriting.net/features/noun_3d%20modeling_1885342.svg/features/noun_3d%20modeling_188534... https://zenwriting.net/features/noun_3d%20modeling_1885342.svg — 200 — 2.2 KiB — 49 ms — h3https://zenwriting.net/cdn-cgi/scripts/5c5dd728/cloudflare-static/email-decode.min.js/cdn-cgi/scripts/5c5dd728/cloudflar... https://zenwriting.net/cdn-cgi/scripts/5c5dd728/cloudflare-static/email-decode.min.js — 200 — 1.0 KiB — 20 ms — h3https://zenwriting.net/js/scripts.min.bf1e1f7ae8e03db5f012356e825843facdff51c0a559cb0d27fe2bbe1db405c2.js/js/scripts.min.bf1e1f7ae8e03db5f01... https://zenwriting.net/js/scripts.min.bf1e1f7ae8e03db5f012356e825843facdff51c0a559cb0d27fe2bbe1db405c2.js — 200 — 653 B — 46 ms — h3https://fonts.googleapis.com/css?family=Lora:400,700|Open+Sans:300,400,700fonts.googleapis.com/css?family=Lor... https://fonts.googleapis.com/css?family=Lora:400,700|Open+Sans:300,400,700 — 200 — 2.4 KiB — 77 ms — h2https://zenwriting.net/images/undraw_taking_notes_tjaf.svg/images/undraw_taking_notes_tjaf.sv... https://zenwriting.net/images/undraw_taking_notes_tjaf.svg — 200 — 11.1 KiB — 28 ms — h3https://fonts.gstatic.com/s/lora/v37/0QIvMX1D_JOuMwr7I_FMl_E.woff2fonts.gstatic.com/s/lora/v37/0QIvMX... https://fonts.gstatic.com/s/lora/v37/0QIvMX1D_JOuMwr7I_FMl_E.woff2 — 200 — 36.9 KiB — 56 ms — h3https://fonts.gstatic.com/s/opensans/v44/memvYaGs126MiZpBA-UvWbX2vVnXBbObj2OVTS-mu0SC55I.woff2fonts.gstatic.com/s/opensans/v44/me... https://fonts.gstatic.com/s/opensans/v44/memvYaGs126MiZpBA-UvWbX2vVnXBbObj2OVTS-mu0SC55I.woff2 — 200 — 42.0 KiB — 60 ms — h3https://zenwriting.net/favicon.png/favicon.png https://zenwriting.net/favicon.png — 200 — 8.6 KiB — 26 ms — h3
HTML JavaScript CSS Images Fonts XHR/Fetch Other
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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