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https://wayfair.com

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
2
PASS
2
INFO
0
Device:
Mobile Desktop
Checks
6
2 PASS 2 REVIEW 2 FIX
F
CO2 Per Page Load
Action
4.06g CO2 per view
FIX
4.06g CO2 per view
Critical::
4.06g CO2 per page view
This page transfers 17.2 MB, producing an estimated 4.06g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.10g, network 0.84g, end-user device 3.12g.
Got: 4.06g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 487.5 kg CO2/year
With 10,000 page views per month, this page would generate approximately 487.5 kg of CO2 annually — equivalent to charging 60933 smartphones.
Info::
Green hosting reduces data center emissions

4.06g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 5% of websites

Sustainable Web Design model v4 · Page size: 17.2 MB

Your site
4.06g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.10g
Network
0.84g
End-user device
3.12g
At 10,000 monthly views: Monthly: 40.6 kg · Annual: 487.5 kg · ≈ 60933 smartphone charges
F
Carbon Budget
Action
95th percentile
FIX
95th percentile
Warning::
4.06g 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

4.06g

95th percentile

Cleaner than 5% of websites

✗ Above the median website

vs Median 577% more
vs Target 712% more
B
Transfer Efficiency
88% efficient
REVIEW
88% efficient
Info::
Transfer efficiency: 88%
An estimated 2024 KB (12%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 2024 KB of unused JavaScript. This wasted data produces 0.47g of unnecessary CO2 per page view.
88% efficient

Total waste: 2024 KB (12% of page weight)

Unused JS 2024 KB

0.47g unnecessary CO2 per visit

Actual transfer 17574 KB
Theoretical minimum 15550 KB
Potential savings 2024 KB (0.47g 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 Not identified✗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 137 KB (vs 17574 KB first visit). 420 of 421 resources are served from browser cache, saving 4.03g CO2 per repeat visit.
Info::
Repeat visit: 0.03g CO2 (first visit: 4.06g)
First visit
17574 KB
Repeat visit
137 KB

99% reduction on repeat visits

Saving 4.03g CO2 per returning visitor

420 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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