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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
81
GRADE
B
FIX
0
REVIEW
4
PASS
2
INFO
0
Device:
Mobile Desktop
Checks
6
2 PASS 4 REVIEW
B
CO2 Per Page Load
0.58g CO2 per view
REVIEW
0.58g CO2 per view
Info::
0.58g CO2 per page view
This page transfers 2.4 MB, producing an estimated 0.58g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.01g, network 0.12g, end-user device 0.44g.
Got: 0.58g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 69.1 kg CO2/year
With 10,000 page views per month, this page would generate approximately 69.1 kg of CO2 annually — equivalent to charging 8641 smartphones.
Info::
Green hosting reduces data center emissions

0.58g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 53% of websites

Sustainable Web Design model v4 · Page size: 2.4 MB

Your site
0.58g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.01g
Network
0.12g
End-user device
0.44g
At 10,000 monthly views: Monthly: 5.8 kg · Annual: 69.1 kg · ≈ 8641 smartphone charges
B
Carbon Budget
47th percentile
REVIEW
47th percentile
Info::
0.58g CO2 — below the median website (0.60g)
Better than an estimated 53% of websites, but above the sustainability target of 0.50g. Reducing page weight would help reach the target.
Info::
Estimated 47th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.58g

47th percentile

Cleaner than 53% of websites

✗ Above the median website

vs Median 4% cleaner ✓
vs Target 15% more
B
Transfer Efficiency
86% efficient
REVIEW
86% efficient
Info::
Transfer efficiency: 86%
An estimated 351 KB (14%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 351 KB of unused JavaScript. This wasted data produces 0.08g of unnecessary CO2 per page view.
86% efficient

Total waste: 351 KB (14% of page weight)

Unused JS 351 KB

0.08g unnecessary CO2 per visit

Actual transfer 2492 KB
Theoretical minimum 2140 KB
Potential savings 351 KB (0.08g 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::
Fastly CDN uses renewable energy
Since most traffic is served through the CDN, the majority of data transfer energy is renewable.
Info::
Fastly: 100% renewable energy for edge network
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 Acquia Cloud Platform✗CDN Fastly✓

Fastly: 100% renewable energy for edge network

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 36 KB (vs 2492 KB first visit). 107 of 111 resources are served from browser cache, saving 0.57g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 0.58g)
First visit
2492 KB
Repeat visit
36 KB

99% reduction on repeat visits

Saving 0.57g CO2 per returning visitor

107 resources served from cache · 4 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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