https://www.sazimebudoucnost.cz
Sustainability
· 8 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.SCORE
70
GRADE
C
FIX
1
REVIEW
5
PASS
1
INFO
1
Checks
81 PASS 5 REVIEW 1 FIX
DGreen HostingActionNot greenFIX
Green Hosting
ActionNot green
Not green
Info::
No confirmed renewable energy commitment detected
Consider providers like Cloudflare, Google Cloud, or Vercel that match 100% of their energy use with renewables.
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 HostingNot Green Hosted
Hosting Microsoft IIS✗CDN Not identified✗
Based on known provider commitments. Verify at thegreenwebfoundation.org
BCO2 Per Page Load0.61g CO2 per viewREVIEW
CO2 Per Page Load
0.61g CO2 per view
0.61g CO2 per view
Info::
0.61g CO2 per page view
This page transfers 2.1 MB, producing an estimated 0.61g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.11g, network 0.10g, end-user device 0.39g.
Got: 0.61g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 72.8 kg CO2/year
With 10,000 page views per month, this page would generate approximately 72.8 kg of CO2 annually — equivalent to charging 9096 smartphones.
0.61g
Carbon Footprint per page view
✗ Above sustainability target (0.50g)
Cleaner than 50% of websites
Sustainable Web Design model v4 · Page size: 2.1 MB
Your site
0.61g
Top 10%
0.20g
Target
0.50g
Median website
0.60g
Energy Breakdown
Data center
0.11g
Network
0.10g
End-user device
0.39g
At 10,000 monthly views: Monthly: 6.1 kg · Annual: 72.8 kg · ≈ 9096 smartphone charges
BCarbon Budget50th percentileREVIEW
Carbon Budget
50th percentile
50th percentile
Warning::
0.61g CO2 — above the median website (0.60g)
Heavier than an estimated 50% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 50th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website
0.61g
50th percentile
Cleaner than 50% of websites
✗ Above the median website
vs Median 1% more
vs Target 21% more
CTransfer EfficiencyAction70% efficientREVIEW
Transfer Efficiency
Action70% efficient
70% efficient
Warning::
Transfer efficiency: 70%
An estimated 648 KB (30%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 648 KB of unused JavaScript. This wasted data produces 0.18g of unnecessary CO2 per page view.
Total waste: 648 KB (30% of page weight)
Unused JS 648 KB
0.18g unnecessary CO2 per visit
Actual transfer 2192 KB
Theoretical minimum 1544 KB
Potential savings 648 KB (0.18g CO2)
See Deep Analysis sections above for specific optimizations.
CWeb Font Weight VariantsAction8 font weights loaded across 1 famil(y/ies)REVIEW
Web Font Weight Variants
Action8 font weights loaded across 1 famil(y/ies)
8 font weights loaded across 1 famil(y/ies)
Warning::
8 font weights loaded -- likely 100+ KB of unused payload
Loading 8 font weights typically transfers 200-400 KB just for fonts. Most pages legitimately use 2-3 weights (regular + bold, maybe medium). Audit which weights your stylesheet actually applies and trim the Google Fonts URL accordingly. Affected families: Istok Web.
CGreen HostingActionWhether the site is served from green-energy infrastructureREVIEW
Green Hosting
ActionWhether the site is served from green-energy infrastructure
Green Hosting
No green hosting detected
A+Repeat Visit Weight98% cachedPASS
Repeat Visit Weight
98% cached
98% cached
Info::
98% reduction on repeat visits
Returning visitors download only 39 KB (vs 2192 KB first visit). 46 of 47 resources are served from browser cache, saving 0.60g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 0.61g)
First visit
2192 KB
Repeat visit
39 KB
98% reduction on repeat visits
Saving 0.60g CO2 per returning visitor
46 resources served from cache · 1 resources re-downloaded
Image Optimization62 images, 157 KB total, 0 KB wastedINFO
Image Optimization
62 images, 157 KB total, 0 KB wasted
Image Optimization Audit
Total Images
62
Total Size
157 KB
9 missing alt text 61 missing dimensions 61 missing lazy loading
All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.