Skip to content
https://mapy.cz

Sustainability

· 6 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
56
GRADE
D
FIX
3
REVIEW
2
PASS
1
INFO
0
Device:
Mobile Desktop
Checks
6
1 PASS 2 REVIEW 3 FIX
F
CO2 Per Page Load
Action
1.54g CO2 per view
FIX
1.54g CO2 per view
Warning::
1.54g CO2 per page view
This page transfers 5.4 MB, producing an estimated 1.54g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.29g, network 0.27g, end-user device 0.99g.
Got: 1.54g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 184.9 kg CO2/year
With 10,000 page views per month, this page would generate approximately 184.9 kg of CO2 annually — equivalent to charging 23110 smartphones.

1.54g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 24% of websites

Sustainable Web Design model v4 · Page size: 5.4 MB

Your site
1.54g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.29g
Network
0.27g
End-user device
0.99g
At 10,000 monthly views: Monthly: 15.4 kg · Annual: 184.9 kg · ≈ 23110 smartphone charges
D
Green Hosting
Action
Not green
FIX
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 Snowplow Analytics✗CDN Not identified✗

Based on known provider commitments. Verify at thegreenwebfoundation.org

F
Carbon Budget
Action
76th percentile
FIX
76th percentile
Warning::
1.54g CO2 — above the median website (0.60g)
Heavier than an estimated 24% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 76th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.54g

76th percentile

Cleaner than 24% of websites

✗ Above the median website

vs Median 157% more
vs Target 208% more
B
Transfer Efficiency
78% efficient
REVIEW
78% efficient
Info::
Transfer efficiency: 78%
An estimated 1230 KB (22%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 1230 KB of unused JavaScript. This wasted data produces 0.34g of unnecessary CO2 per page view.
78% efficient

Total waste: 1230 KB (22% of page weight)

Unused JS 1230 KB

0.34g unnecessary CO2 per visit

Actual transfer 5570 KB
Theoretical minimum 4340 KB
Potential savings 1230 KB (0.34g 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+
Repeat Visit Weight
100% cached
PASS
100% cached
Info::
100% reduction on repeat visits
Returning visitors download only 6 KB (vs 5570 KB first visit). 131 of 133 resources are served from browser cache, saving 1.54g CO2 per repeat visit.
Info::
Repeat visit: 0.00g CO2 (first visit: 1.54g)
First visit
5570 KB
Repeat visit
6 KB

100% reduction on repeat visits

Saving 1.54g CO2 per returning visitor

131 resources served from cache · 2 resources re-downloaded

All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.

Send Feedback