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https://otter.ai

Sustainability

· 6 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
63
GRADE
D
FIX
2
REVIEW
1
PASS
3
INFO
0
Device:
Mobile Desktop
Checks
6
3 PASS 1 REVIEW 2 FIX
F
CO2 Per Page Load
Action
4.29g CO2 per view
FIX
4.29g CO2 per view
Critical::
4.29g CO2 per page view
This page transfers 18.1 MB, producing an estimated 4.29g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.11g, network 0.89g, end-user device 3.30g.
Got: 4.29g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 515.4 kg CO2/year
With 10,000 page views per month, this page would generate approximately 515.4 kg of CO2 annually — equivalent to charging 64423 smartphones.
Info::
Green hosting reduces data center emissions

4.29g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 5% of websites

Sustainable Web Design model v4 · Page size: 18.1 MB

Your site
4.29g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.11g
Network
0.89g
End-user device
3.30g
At 10,000 monthly views: Monthly: 42.9 kg · Annual: 515.4 kg · ≈ 64423 smartphone charges
F
Carbon Budget
Action
95th percentile
FIX
95th percentile
Warning::
4.29g 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

4.29g

95th percentile

Cleaner than 5% of websites

✗ Above the median website

vs Median 616% more
vs Target 759% more
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
100% cached
PASS
100% cached
Info::
100% reduction on repeat visits
Returning visitors download only 66 KB (vs 18581 KB first visit). 238 of 246 resources are served from browser cache, saving 4.28g CO2 per repeat visit.
Info::
Repeat visit: 0.02g CO2 (first visit: 4.29g)
First visit
18581 KB
Repeat visit
66 KB

100% reduction on repeat visits

Saving 4.28g CO2 per returning visitor

238 resources served from cache · 8 resources re-downloaded

A+
Transfer Efficiency
98% efficient
PASS
98% efficient
Info::
Transfer efficiency: 98%
Only 376 KB of potential savings identified. Your page is well-optimized for size.
98% efficient

Total waste: 376 KB (2% of page weight)

Unused JS 376 KB

0.09g unnecessary CO2 per visit

Actual transfer 18581 KB
Theoretical minimum 18204 KB
Potential savings 376 KB (0.09g CO2)

See Deep Analysis sections above for specific optimizations.

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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