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Sustainability

· 6 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
72
GRADE
C
FIX
1
REVIEW
2
PASS
3
INFO
0
Device:
Mobile Desktop
Checks
6
3 PASS 2 REVIEW 1 FIX
F
Transfer Efficiency
Action
0% efficient
FIX
0% efficient
Critical::
Transfer efficiency: 0%
An estimated 3300 KB (100%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 3300 KB of unused JavaScript. This wasted data produces 0.76g of unnecessary CO2 per page view.
0% efficient

Total waste: 3300 KB (100% of page weight)

Unused JS 3300 KB

0.76g unnecessary CO2 per visit

Actual transfer 2334 KB
Theoretical minimum 0 KB
Potential savings 3300 KB (0.76g CO2)

See Deep Analysis sections above for specific optimizations.

B
CO2 Per Page Load
0.54g CO2 per view
REVIEW
0.54g CO2 per view
Info::
0.54g CO2 per page view
This page transfers 2.3 MB, producing an estimated 0.54g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.01g, network 0.11g, end-user device 0.41g.
Got: 0.54g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 64.7 kg CO2/year
With 10,000 page views per month, this page would generate approximately 64.7 kg of CO2 annually — equivalent to charging 8092 smartphones.
Info::
Green hosting reduces data center emissions

0.54g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 57% of websites

Sustainable Web Design model v4 · Page size: 2.3 MB

Your site
0.54g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.01g
Network
0.11g
End-user device
0.41g
At 10,000 monthly views: Monthly: 5.4 kg · Annual: 64.7 kg · ≈ 8092 smartphone charges
B
Carbon Budget
43th percentile
REVIEW
43th percentile
Info::
0.54g CO2 — below the median website (0.60g)
Better than an estimated 57% of websites, but above the sustainability target of 0.50g. Reducing page weight would help reach the target.
Info::
Estimated 43th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.54g

43rd percentile

Cleaner than 57% of websites

✗ Above the median website

vs Median 10% cleaner ✓
vs Target 8% more
A+
Green Hosting
Green (both)
PASS
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 Weight
88% cached
PASS
88% cached
Info::
88% reduction on repeat visits
Returning visitors download only 273 KB (vs 2334 KB first visit). 192 of 205 resources are served from browser cache, saving 0.48g CO2 per repeat visit.
Info::
Repeat visit: 0.06g CO2 (first visit: 0.54g)
First visit
2334 KB
Repeat visit
273 KB

88% reduction on repeat visits

Saving 0.48g CO2 per returning visitor

192 resources served from cache · 13 resources re-downloaded

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

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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