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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
62
GRADE
D
FIX
2
REVIEW
2
PASS
2
INFO
0
Device:
Mobile Desktop
Checks
6
2 PASS 2 REVIEW 2 FIX
F
CO2 Per Page Load
Action
2.33g CO2 per view
FIX
2.33g CO2 per view
Critical::
2.33g CO2 per page view
This page transfers 9.9 MB, producing an estimated 2.33g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.06g, network 0.48g, end-user device 1.79g.
Got: 2.33g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 279.9 kg CO2/year
With 10,000 page views per month, this page would generate approximately 279.9 kg of CO2 annually — equivalent to charging 34983 smartphones.
Info::
Green hosting reduces data center emissions

2.33g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 5% of websites

Sustainable Web Design model v4 · Page size: 9.9 MB

Your site
2.33g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.06g
Network
0.48g
End-user device
1.79g
At 10,000 monthly views: Monthly: 23.3 kg · Annual: 279.9 kg · ≈ 34983 smartphone charges
F
Carbon Budget
Action
95th percentile
FIX
95th percentile
Warning::
2.33g CO2 — above the median website (0.60g)
Heavier than an estimated 5% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 95th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

2.33g

95th percentile

Cleaner than 5% of websites

✗ Above the median website

vs Median 289% more
vs Target 366% more
B
Transfer Efficiency
81% efficient
REVIEW
81% efficient
Info::
Transfer efficiency: 81%
An estimated 1909 KB (19%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 1909 KB of unused JavaScript. This wasted data produces 0.44g of unnecessary CO2 per page view.
81% efficient

Total waste: 1909 KB (19% of page weight)

Unused JS 1909 KB

0.44g unnecessary CO2 per visit

Actual transfer 10090 KB
Theoretical minimum 8180 KB
Potential savings 1909 KB (0.44g CO2)

See Deep Analysis sections above for specific optimizations.

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

Green Hosting

No green hosting detected

A
Green Hosting
Green (cdn)
PASS
Green (cdn)
Info::
Cloudflare CDN uses renewable energy
Since most traffic is served through the CDN, the majority of data transfer energy is renewable.
Info::
AWS: Renewable energy varies by region; committed to 100% by 2025
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 AWS✗CDN Cloudflare✓

AWS: Renewable energy varies by region; committed to 100% by 2025

Cloudflare: 100% renewable energy for global network since 2019

Based on known provider commitments. Verify at thegreenwebfoundation.org

A+
Repeat Visit Weight
99% cached
PASS
99% cached
Info::
99% reduction on repeat visits
Returning visitors download only 132 KB (vs 10090 KB first visit). 305 of 313 resources are served from browser cache, saving 2.30g CO2 per repeat visit.
Info::
Repeat visit: 0.03g CO2 (first visit: 2.33g)
First visit
10090 KB
Repeat visit
132 KB

99% reduction on repeat visits

Saving 2.30g CO2 per returning visitor

305 resources served from cache · 8 resources re-downloaded

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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