Skip to content
https://firebase.google.com

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
4.11g CO2 per view
FIX
4.11g CO2 per view
Critical::
4.11g CO2 per page view
This page transfers 17.4 MB, producing an estimated 4.11g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.10g, network 0.85g, end-user device 3.15g.
Got: 4.11g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 492.9 kg CO2/year
With 10,000 page views per month, this page would generate approximately 492.9 kg of CO2 annually — equivalent to charging 61610 smartphones.
Info::
Green hosting reduces data center emissions

4.11g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 5% of websites

Sustainable Web Design model v4 · Page size: 17.4 MB

Your site
4.11g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.10g
Network
0.85g
End-user device
3.15g
At 10,000 monthly views: Monthly: 41.1 kg · Annual: 492.9 kg · ≈ 61610 smartphone charges
F
Carbon Budget
Action
95th percentile
FIX
95th percentile
Warning::
4.11g 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

4.11g

95th percentile

Cleaner than 5% of websites

✗ Above the median website

vs Median 585% more
vs Target 721% more
B
Green Hosting
Green (hosting)
REVIEW
Green (hosting)
Info::
Google Cloud uses renewable energy
Info::
Google Cloud: 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 Google Cloud✓CDN Not identified✗

Google Cloud: Verified by the Green Web Foundation

Based on known provider commitments. Verify at thegreenwebfoundation.org

A+
Repeat Visit Weight
99% cached
PASS
99% cached
Info::
99% reduction on repeat visits
Returning visitors download only 101 KB (vs 17769 KB first visit). 114 of 117 resources are served from browser cache, saving 4.08g CO2 per repeat visit.
Info::
Repeat visit: 0.02g CO2 (first visit: 4.11g)
First visit
17769 KB
Repeat visit
101 KB

99% reduction on repeat visits

Saving 4.08g CO2 per returning visitor

114 resources served from cache · 3 resources re-downloaded

A+
Transfer Efficiency
96% efficient
PASS
96% efficient
Info::
Transfer efficiency: 96%
Only 695 KB of potential savings identified. Your page is well-optimized for size.
96% efficient

Total waste: 695 KB (4% of page weight)

Unused JS 695 KB

0.16g unnecessary CO2 per visit

Actual transfer 17769 KB
Theoretical minimum 17074 KB
Potential savings 695 KB (0.16g 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: Google Cloud

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

Send Feedback