https://lagunatools.com
Sustainability
· 8 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.SCORE
69
GRADE
D
FIX
2
REVIEW
2
PASS
3
INFO
1
Checks
83 PASS 2 REVIEW 2 FIX
FCO2 Per Page LoadAction2.49g CO2 per viewFIX
CO2 Per Page Load
Action2.49g CO2 per view
2.49g CO2 per view
Critical::
2.49g CO2 per page view
This page transfers 10.5 MB, producing an estimated 2.49g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.06g, network 0.51g, end-user device 1.91g.
Got: 2.49g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 298.4 kg CO2/year
With 10,000 page views per month, this page would generate approximately 298.4 kg of CO2 annually — equivalent to charging 37299 smartphones.
Info::
Green hosting reduces data center emissions
2.49g
Carbon Footprint per page view
✗ Above sustainability target (0.50g)
Cleaner than 5% of websites
Sustainable Web Design model v4 · Page size: 10.5 MB
Your site
2.49g
Top 10%
0.20g
Target
0.50g
Median website
0.60g
Energy Breakdown
Data center
0.06g
Network
0.51g
End-user device
1.91g
At 10,000 monthly views: Monthly: 24.9 kg · Annual: 298.4 kg · ≈ 37299 smartphone charges
FCarbon BudgetAction95th percentileFIX
Carbon Budget
Action95th percentile
95th percentile
Warning::
2.49g 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
2.49g
95th percentile
Cleaner than 5% of websites
✗ Above the median website
vs Median 314% more
vs Target 397% more
BTransfer Efficiency85% efficientREVIEW
Transfer Efficiency
85% efficient
85% efficient
Info::
Transfer efficiency: 85%
An estimated 1586 KB (15%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 1586 KB of unused JavaScript. This wasted data produces 0.37g of unnecessary CO2 per page view.
Total waste: 1586 KB (15% of page weight)
Unused JS 1586 KB
0.37g unnecessary CO2 per visit
Actual transfer 10758 KB
Theoretical minimum 9171 KB
Potential savings 1586 KB (0.37g 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: Cloudflare, CDN: Cloudflare
Info::
Cloudflare: 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 Cloudflare✓CDN Cloudflare✓
Cloudflare: 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 188 KB (vs 10758 KB first visit). 375 of 381 resources are served from browser cache, saving 2.44g CO2 per repeat visit.
Info::
Repeat visit: 0.04g CO2 (first visit: 2.49g)
First visit
10758 KB
Repeat visit
188 KB
98% reduction on repeat visits
Saving 2.44g CO2 per returning visitor
375 resources served from cache · 6 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 Optimization82 images, 1874 KB total, 284 KB wastedINFO
Image Optimization
82 images, 1874 KB total, 284 KB wasted
Image Optimization Audit
Total Images
82
Total Size
1874 KB
Oversized
5
Wasted
284 KB
3 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.