https://ClucktheWeb.com
Sustainability
· 8 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.SCORE
93
GRADE
A
FIX
0
REVIEW
1
PASS
6
INFO
1
Checks
86 PASS 1 REVIEW
BWeb Font Weight VariantsNo detectable Google Fonts weightsREVIEW
Web Font Weight Variants
No detectable Google Fonts weights
No detectable Google Fonts weights
Info::
No detectable Google Fonts weights
The analyzer detects font weights via Google Fonts URL parameters (~70% of font-using sites). Self-hosted fonts and non-Google CDN fonts aren't visible to URL-based detection. If you self-host fonts, manually audit how many @font-face weights you ship -- 2-3 weights per family is typically enough; 5+ is usually unused payload.
ACO2 Per Page Load0.23g CO2 per viewPASS
CO2 Per Page Load
0.23g CO2 per view
0.23g CO2 per view
Info::
0.23g CO2 per page view
This page transfers 1.0 MB, producing an estimated 0.23g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.01g, network 0.05g, end-user device 0.17g.
Got: 0.23g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 27.1 kg CO2/year
With 10,000 page views per month, this page would generate approximately 27.1 kg of CO2 annually — equivalent to charging 3381 smartphones.
Info::
Green hosting reduces data center emissions
0.23g
Carbon Footprint per page view
✓ Below sustainability target (0.50g)
Cleaner than 88% of websites
Sustainable Web Design model v4 · Page size: 1.0 MB
Your site
0.23g
Top 10%
0.20g
Target
0.50g
Median website
0.60g
Energy Breakdown
Data center
0.01g
Network
0.05g
End-user device
0.17g
At 10,000 monthly views: Monthly: 2.3 kg · Annual: 27.1 kg · ≈ 3381 smartphone charges
A+Green HostingGreen (both)PASS
Green Hosting
Green (both)
Green (both)
Info::
Both hosting and CDN use renewable energy
Got: Hosting: Cloudflare, CDN: Cloudflare
Info::
Cloudflare: Verified by the Green Web Foundation
Info::
Cloudflare: 100% renewable energy for global network since 2019
Info::
Green hosting status based on known provider commitments
Green hosting detection uses a curated database of provider renewable energy commitments. This is not a real-time verification. For authoritative checks, visit thegreenwebfoundation.org.
Green Hosting✓ Green Hosted
Hosting Cloudflare✓CDN Cloudflare✓
Cloudflare: Verified by the Green Web Foundation
Cloudflare: 100% renewable energy for global network since 2019
Based on known provider commitments. Verify at thegreenwebfoundation.org
A+Repeat Visit Weight96% cachedPASS
Repeat Visit Weight
96% cached
96% cached
Info::
96% reduction on repeat visits
Returning visitors download only 34 KB (vs 975 KB first visit). 28 of 29 resources are served from browser cache, saving 0.22g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 0.23g)
First visit
975 KB
Repeat visit
34 KB
96% reduction on repeat visits
Saving 0.22g CO2 per returning visitor
28 resources served from cache · 1 resources re-downloaded
ACarbon Budget12th percentilePASS
Carbon Budget
12th percentile
12th percentile
Info::
0.23g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 88% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 12th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website
0.23g
12th percentile
Cleaner than 88% of websites
✓ Below the Web Sustainability Guidelines target
vs Median 62% cleaner ✓
vs Target 55% cleaner ✓
A+Transfer Efficiency97% efficientPASS
Transfer Efficiency
97% efficient
97% efficient
Info::
Transfer efficiency: 97%
Only 25 KB of potential savings identified. Your page is well-optimized for size.
Total waste: 25 KB (3% of page weight)
Unused JS 25 KB
0.01g unnecessary CO2 per visit
Actual transfer 975 KB
Theoretical minimum 949 KB
Potential savings 25 KB (0.01g CO2)
See Deep Analysis sections above for specific optimizations.
A+Green HostingWhether the site is served from green-energy infrastructurePASS
Green Hosting
Whether the site is served from green-energy infrastructure
Green Hosting
This site is hosted on green energy infrastructure
Provider: Cloudflare
Image Optimization2 images, 517 KB total, 0 KB wastedINFO
Image Optimization
2 images, 517 KB total, 0 KB wasted
Image Optimization Audit
Total Images
2
Total Size
517 KB
All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.