https://gibsonlook.com
Sustainability
· 8 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.SCORE
71
GRADE
C
FIX
2
REVIEW
2
PASS
3
INFO
1
Checks
83 PASS 2 REVIEW 2 FIX
FCO2 Per Page LoadAction1.90g CO2 per viewFIX
CO2 Per Page Load
Action1.90g CO2 per view
1.90g CO2 per view
Warning::
1.90g CO2 per page view
This page transfers 8.0 MB, producing an estimated 1.90g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.05g, network 0.39g, end-user device 1.46g.
Got: 1.90g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 227.5 kg CO2/year
With 10,000 page views per month, this page would generate approximately 227.5 kg of CO2 annually — equivalent to charging 28434 smartphones.
Info::
Green hosting reduces data center emissions
1.90g
Carbon Footprint per page view
✗ Above sustainability target (0.50g)
Cleaner than 13% of websites
Sustainable Web Design model v4 · Page size: 8.0 MB
Your site
1.90g
Top 10%
0.20g
Target
0.50g
Median website
0.60g
Energy Breakdown
Data center
0.05g
Network
0.39g
End-user device
1.46g
At 10,000 monthly views: Monthly: 19.0 kg · Annual: 227.5 kg · ≈ 28434 smartphone charges
FCarbon BudgetAction87th percentileFIX
Carbon Budget
Action87th percentile
87th percentile
Warning::
1.90g CO2 — above the median website (0.60g)
Heavier than an estimated 13% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 87th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website
1.90g
87th percentile
Cleaner than 13% of websites
✗ Above the median website
vs Median 216% more
vs Target 279% more
BTransfer Efficiency77% efficientREVIEW
Transfer Efficiency
77% efficient
77% efficient
Info::
Transfer efficiency: 77%
An estimated 1904 KB (23%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 1904 KB of unused JavaScript. This wasted data produces 0.44g of unnecessary CO2 per page view.
Total waste: 1904 KB (23% of page weight)
Unused JS 1904 KB
0.44g unnecessary CO2 per visit
Actual transfer 8201 KB
Theoretical minimum 6296 KB
Potential savings 1904 KB (0.44g CO2)
See Deep Analysis sections above for specific optimizations.
BWeb Font Weight VariantsNo detectable Google Fonts weightsREVIEW
Web Font Weight Variants
No detectable Google Fonts weights
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.
A+Green HostingGreen (both)PASS
Green Hosting
Green (both)
Green (both)
Info::
Both hosting and CDN use renewable energy
Got: Hosting: GoDaddy, CDN: Cloudflare
Info::
GoDaddy: 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 GoDaddy✓CDN Cloudflare✓
GoDaddy: 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 Weight98% cachedPASS
Repeat Visit Weight
98% cached
98% cached
Info::
98% reduction on repeat visits
Returning visitors download only 137 KB (vs 8201 KB first visit). 691 of 700 resources are served from browser cache, saving 1.86g CO2 per repeat visit.
Info::
Repeat visit: 0.03g CO2 (first visit: 1.90g)
First visit
8201 KB
Repeat visit
137 KB
98% reduction on repeat visits
Saving 1.86g CO2 per returning visitor
691 resources served from cache · 9 resources re-downloaded
A+Green HostingWhether the site is served from green-energy infrastructurePASS
Green Hosting
Whether the site is served from green-energy infrastructure
Green Hosting
This site is hosted on green energy infrastructure
Provider: Cloudflare
Image Optimization22 images, 458 KB total, 0 KB wastedINFO
Image Optimization
22 images, 458 KB total, 0 KB wasted
Image Optimization Audit
Total Images
22
Total Size
458 KB
16 missing dimensions 14 missing lazy loading
All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.