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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
80
GRADE
B
FIX
1
REVIEW
3
PASS
2
INFO
0
Device:
Mobile Desktop
Checks
6
2 PASS 3 REVIEW 1 FIX
D
Carbon Budget
Action
51th percentile
FIX
51th percentile
Warning::
0.65g CO2 — above the median website (0.60g)
Heavier than an estimated 49% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 51th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.65g

51st percentile

Cleaner than 49% of websites

✗ Above the median website

vs Median 8% more
vs Target 30% more
B
CO2 Per Page Load
0.65g CO2 per view
REVIEW
0.65g CO2 per view
Info::
0.65g CO2 per page view
This page transfers 2.7 MB, producing an estimated 0.65g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.02g, network 0.13g, end-user device 0.50g.
Got: 0.65g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 78.0 kg CO2/year
With 10,000 page views per month, this page would generate approximately 78.0 kg of CO2 annually — equivalent to charging 9746 smartphones.
Info::
Green hosting reduces data center emissions

0.65g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 49% of websites

Sustainable Web Design model v4 · Page size: 2.7 MB

Your site
0.65g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.02g
Network
0.13g
End-user device
0.50g
At 10,000 monthly views: Monthly: 6.5 kg · Annual: 78.0 kg · ≈ 9746 smartphone charges
B
Green Hosting
Green (hosting)
REVIEW
Green (hosting)
Info::
Google Cloud uses renewable energy
Info::
Google Cloud: Verified by the Green Web Foundation
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 Google Cloud✓CDN Not identified✗

Google Cloud: Verified by the Green Web Foundation

Based on known provider commitments. Verify at thegreenwebfoundation.org

B
Transfer Efficiency
83% efficient
REVIEW
83% efficient
Info::
Transfer efficiency: 83%
An estimated 467 KB (17%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 467 KB of unused JavaScript. This wasted data produces 0.11g of unnecessary CO2 per page view.
83% efficient

Total waste: 467 KB (17% of page weight)

Unused JS 467 KB

0.11g unnecessary CO2 per visit

Actual transfer 2811 KB
Theoretical minimum 2343 KB
Potential savings 467 KB (0.11g CO2)

See Deep Analysis sections above for specific optimizations.

A+
Repeat Visit Weight
98% cached
PASS
98% cached
Info::
98% reduction on repeat visits
Returning visitors download only 62 KB (vs 2811 KB first visit). 95 of 99 resources are served from browser cache, saving 0.64g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 0.65g)
First visit
2811 KB
Repeat visit
62 KB

98% reduction on repeat visits

Saving 0.64g CO2 per returning visitor

95 resources served from cache · 4 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: Google Cloud

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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