Skip to content
https://bing.com

Sustainability

· 8 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
75
GRADE
C
FIX
2
REVIEW
2
PASS
3
INFO
1
Checks
8
3 PASS 2 REVIEW 2 FIX
D
Green Hosting
Action
Unknown
FIX
Unknown
Info::
Hosting provider could not be identified
Without knowing the provider, we cannot determine their energy sourcing. Check with your hosting provider about their renewable energy commitments.
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 HostingUnable to Determine
Hosting Not identifiedCDN Not identified

Based on known provider commitments. Verify at thegreenwebfoundation.org

D
Transfer Efficiency
Action
60% efficient
FIX
60% efficient
Warning::
Transfer efficiency: 60%
An estimated 383 KB (40%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 383 KB of unused JavaScript. This wasted data produces 0.11g of unnecessary CO2 per page view.
60% efficient

Total waste: 383 KB (40% of page weight)

Unused JS 383 KB

0.11g unnecessary CO2 per visit

Actual transfer 953 KB
Theoretical minimum 570 KB
Potential savings 383 KB (0.11g CO2)

See Deep Analysis sections above for specific optimizations.

B
Web Font Weight Variants
No detectable Google Fonts weights
REVIEW
No detectable Google Fonts weights
Info::
No detectable Google Fonts weights
The analyzer detects font weights via Google Fonts URL parameters (~70% of font-using sites). Self-hosted fonts and non-Google CDN fonts aren't visible to URL-based detection. If you self-host fonts, manually audit how many @font-face weights you ship -- 2-3 weights per family is typically enough; 5+ is usually unused payload.
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A
CO2 Per Page Load
0.26g CO2 per view
PASS
0.26g CO2 per view
Info::
0.26g CO2 per page view
This page transfers 0.9 MB, producing an estimated 0.26g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.05g, network 0.05g, end-user device 0.17g.
Got: 0.26g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 31.6 kg CO2/year
With 10,000 page views per month, this page would generate approximately 31.6 kg of CO2 annually — equivalent to charging 3955 smartphones.

0.26g

Carbon Footprint per page view

Below sustainability target (0.50g)

Cleaner than 84% of websites

Sustainable Web Design model v4 · Page size: 0.9 MB

Your site
0.26g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.05g
Network
0.05g
End-user device
0.17g
At 10,000 monthly views: Monthly: 2.6 kg · Annual: 31.6 kg · ≈ 3955 smartphone charges
A+
Repeat Visit Weight
94% cached
PASS
94% cached
Info::
94% reduction on repeat visits
Returning visitors download only 59 KB (vs 953 KB first visit). 96 of 99 resources are served from browser cache, saving 0.25g CO2 per repeat visit.
Info::
Repeat visit: 0.02g CO2 (first visit: 0.26g)
First visit
953 KB
Repeat visit
59 KB

94% reduction on repeat visits

Saving 0.25g CO2 per returning visitor

96 resources served from cache · 3 resources re-downloaded

A
Carbon Budget
16th percentile
PASS
16th percentile
Info::
0.26g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 84% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 16th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.26g

16th percentile

Cleaner than 84% of websites

Below the Web Sustainability Guidelines target

vs Median 56% cleaner ✓
vs Target 47% cleaner ✓
Image Optimization
31 images, 98 KB total, 0 KB wasted
INFO

Image Optimization Audit

Total Images

31

Total Size

98 KB

5 missing alt text 24 missing dimensions 5 missing lazy loading
All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.

Send Feedback