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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
2
REVIEW
0
PASS
4
INFO
0
Device:
Mobile Desktop
Checks
6
4 PASS 2 FIX
D
CO2 Per Page Load
Action
0.89g CO2 per view
FIX
0.89g CO2 per view
Info::
0.89g CO2 per page view
This page transfers 3.8 MB, producing an estimated 0.89g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.02g, network 0.18g, end-user device 0.68g.
Got: 0.89g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 106.8 kg CO2/year
With 10,000 page views per month, this page would generate approximately 106.8 kg of CO2 annually — equivalent to charging 13347 smartphones.
Info::
Green hosting reduces data center emissions

0.89g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 42% of websites

Sustainable Web Design model v4 · Page size: 3.8 MB

Your site
0.89g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.02g
Network
0.18g
End-user device
0.68g
At 10,000 monthly views: Monthly: 8.9 kg · Annual: 106.8 kg · ≈ 13347 smartphone charges
D
Carbon Budget
Action
58th percentile
FIX
58th percentile
Warning::
0.89g CO2 — above the median website (0.60g)
Heavier than an estimated 42% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 58th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.89g

58th percentile

Cleaner than 42% of websites

✗ Above the median website

vs Median 48% more
vs Target 78% more
A+
Green Hosting
Green (both)
PASS
Green (both)
Info::
Both hosting and CDN use renewable energy
Got: Hosting: Google Cloud, CDN: Cloudflare
Info::
Google Cloud: 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 Google Cloud✓CDN Cloudflare✓

Google Cloud: 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
99% cached
PASS
99% cached
Info::
99% reduction on repeat visits
Returning visitors download only 37 KB (vs 3849 KB first visit). 57 of 58 resources are served from browser cache, saving 0.88g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 0.89g)
First visit
3849 KB
Repeat visit
37 KB

99% reduction on repeat visits

Saving 0.88g CO2 per returning visitor

57 resources served from cache · 1 resources re-downloaded

A+
Transfer Efficiency
92% efficient
PASS
92% efficient
Info::
Transfer efficiency: 92%
Only 317 KB of potential savings identified. Your page is well-optimized for size.
92% efficient

Total waste: 317 KB (8% of page weight)

Unused JS 317 KB

0.07g unnecessary CO2 per visit

Actual transfer 3849 KB
Theoretical minimum 3532 KB
Potential savings 317 KB (0.07g CO2)

See Deep Analysis sections above for specific optimizations.

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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