Skip to content
https://lodz.pl

Sustainability

· 6 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
62
GRADE
D
FIX
2
REVIEW
1
PASS
3
INFO
0
Device:
Mobile Desktop
Checks
6
3 PASS 1 REVIEW 2 FIX
F
CO2 Per Page Load
Action
4.87g CO2 per view
FIX
4.87g CO2 per view
Critical::
4.87g CO2 per page view
This page transfers 20.6 MB, producing an estimated 4.87g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.12g, network 1.01g, end-user device 3.74g.
Got: 4.87g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 584.6 kg CO2/year
With 10,000 page views per month, this page would generate approximately 584.6 kg of CO2 annually — equivalent to charging 73071 smartphones.
Info::
Green hosting reduces data center emissions

4.87g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 5% of websites

Sustainable Web Design model v4 · Page size: 20.6 MB

Your site
4.87g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.12g
Network
1.01g
End-user device
3.74g
At 10,000 monthly views: Monthly: 48.7 kg · Annual: 584.6 kg · ≈ 73071 smartphone charges
F
Carbon Budget
Action
95th percentile
FIX
95th percentile
Warning::
4.87g 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

4.87g

95th percentile

Cleaner than 5% of websites

✗ Above the median website

vs Median 712% more
vs Target 874% more
B
Green Hosting
Green (hosting)
REVIEW
Green (hosting)
Info::
Hetzner Online GmbH uses renewable energy
Info::
Hetzner Online GmbH: Verified by the Green Web Foundation
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 Hetzner Online GmbH✓CDN Not identified✗

Hetzner Online GmbH: Verified by the Green Web Foundation

Based on known provider commitments. Verify at thegreenwebfoundation.org

A+
Repeat Visit Weight
98% cached
PASS
98% cached
Info::
98% reduction on repeat visits
Returning visitors download only 320 KB (vs 21075 KB first visit). 344 of 359 resources are served from browser cache, saving 4.80g CO2 per repeat visit.
Info::
Repeat visit: 0.07g CO2 (first visit: 4.87g)
First visit
21075 KB
Repeat visit
320 KB

98% reduction on repeat visits

Saving 4.80g CO2 per returning visitor

344 resources served from cache · 15 resources re-downloaded

A+
Transfer Efficiency
95% efficient
PASS
95% efficient
Info::
Transfer efficiency: 95%
Only 1040 KB of potential savings identified. Your page is well-optimized for size.
95% efficient

Total waste: 1040 KB (5% of page weight)

Unused JS 1040 KB

0.24g unnecessary CO2 per visit

Actual transfer 21075 KB
Theoretical minimum 20035 KB
Potential savings 1040 KB (0.24g CO2)

See Deep Analysis sections above for specific optimizations.

A+
Green Hosting
Whether the site is served from green-energy infrastructure
PASS

Green Hosting

This site is hosted on green energy infrastructure

Provider: Hetzner Online GmbH

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

Send Feedback