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https://uio.no

Sustainability

· 6 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
82
GRADE
B
FIX
1
REVIEW
1
PASS
4
INFO
0
Device:
Mobile Desktop
Checks
6
4 PASS 1 REVIEW 1 FIX
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 Not identified✗CDN Varnish✗

Based on known provider commitments. Verify at thegreenwebfoundation.org

C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A
CO2 Per Page Load
0.24g CO2 per view
PASS
0.24g CO2 per view
Info::
0.24g CO2 per page view
This page transfers 0.8 MB, producing an estimated 0.24g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.04g, network 0.04g, end-user device 0.15g.
Got: 0.24g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 28.7 kg CO2/year
With 10,000 page views per month, this page would generate approximately 28.7 kg of CO2 annually — equivalent to charging 3592 smartphones.

0.24g

Carbon Footprint per page view

✓ Below sustainability target (0.50g)

Cleaner than 87% of websites

Sustainable Web Design model v4 · Page size: 0.8 MB

Your site
0.24g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.04g
Network
0.04g
End-user device
0.15g
At 10,000 monthly views: Monthly: 2.4 kg · Annual: 28.7 kg · ≈ 3592 smartphone charges
A+
Repeat Visit Weight
99% cached
PASS
99% cached
Info::
99% reduction on repeat visits
Returning visitors download only 8 KB (vs 865 KB first visit). 50 of 51 resources are served from browser cache, saving 0.24g CO2 per repeat visit.
Info::
Repeat visit: 0.00g CO2 (first visit: 0.24g)
First visit
865 KB
Repeat visit
8 KB

99% reduction on repeat visits

Saving 0.24g CO2 per returning visitor

50 resources served from cache · 1 resources re-downloaded

A
Carbon Budget
13th percentile
PASS
13th percentile
Info::
0.24g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 87% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 13th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.24g

13th percentile

Cleaner than 87% of websites

✓ Below the Web Sustainability Guidelines target

vs Median 60% cleaner ✓
vs Target 52% cleaner ✓
A+
Transfer Efficiency
95% efficient
PASS
95% efficient
Info::
Transfer efficiency: 95%
Only 44 KB of potential savings identified. Your page is well-optimized for size.
95% efficient

Total waste: 44 KB (5% of page weight)

Unused JS 44 KB

0.01g unnecessary CO2 per visit

Actual transfer 865 KB
Theoretical minimum 821 KB
Potential savings 44 KB (0.01g CO2)

See Deep Analysis sections above for specific optimizations.

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

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