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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
65
GRADE
D
FIX
3
REVIEW
1
PASS
2
INFO
0
Device:
Mobile Desktop
Checks
6
2 PASS 1 REVIEW 3 FIX
D
CO2 Per Page Load
Action
1.08g CO2 per view
FIX
1.08g CO2 per view
Warning::
1.08g CO2 per page view
This page transfers 4.6 MB, producing an estimated 1.08g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.03g, network 0.22g, end-user device 0.83g.
Got: 1.08g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 129.4 kg CO2/year
With 10,000 page views per month, this page would generate approximately 129.4 kg of CO2 annually — equivalent to charging 16172 smartphones.
Info::
Green hosting reduces data center emissions

1.08g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 37% of websites

Sustainable Web Design model v4 · Page size: 4.6 MB

Your site
1.08g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.03g
Network
0.22g
End-user device
0.83g
At 10,000 monthly views: Monthly: 10.8 kg · Annual: 129.4 kg · ≈ 16172 smartphone charges
D
Carbon Budget
Action
63th percentile
FIX
63th percentile
Warning::
1.08g CO2 — above the median website (0.60g)
Heavier than an estimated 37% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 63th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.08g

63rd percentile

Cleaner than 37% of websites

✗ Above the median website

vs Median 80% more
vs Target 116% more
D
Transfer Efficiency
Action
45% efficient
FIX
45% efficient
Critical::
Transfer efficiency: 45%
An estimated 2544 KB (55%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 2544 KB of unused JavaScript. This wasted data produces 0.59g of unnecessary CO2 per page view.
45% efficient

Total waste: 2544 KB (55% of page weight)

Unused JS 2544 KB

0.59g unnecessary CO2 per visit

Actual transfer 4664 KB
Theoretical minimum 2119 KB
Potential savings 2544 KB (0.59g 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::
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 Not identified✗CDN Cloudflare✓

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 29 KB (vs 4664 KB first visit). 126 of 127 resources are served from browser cache, saving 1.07g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 1.08g)
First visit
4664 KB
Repeat visit
29 KB

99% reduction on repeat visits

Saving 1.07g CO2 per returning visitor

126 resources served from cache · 1 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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