All comparisons

London vs San Francisco

Live UV index comparison

London

United-Kingdom

1.1 Est. peak
Low
San Francisco

United-States

3.3 Est. peak
Moderate

Live readings are temporarily unavailable — showing each city's modelled peak UV (historical average / clear-sky). Values update as live data returns.

Based on modelled peaks, San Francisco has the stronger sun — UV 3.3 vs 1.1.

Side-by-side

MetricLondonSan Francisco
UV (peak)1.13.3
Risk levelLowModerate
Today's max UV1.13.3
CountryUnited-KingdomUnited-States
Latitude51.507237.7558
Population11,262,0003,290,197

Monthly UV trend

Average UV index by month, London vs San Francisco.

How this is calculated