Enhanced Fujita rating to Fujita rating (1971)
Type a value in EF scale to get it in F scale instantly.
F3F scale
That's 1.35× as strong as a strong EF2 tornado, while a violent EF4 tornado is 1.1× stronger.
Convert the other way: F scale to EF scale
What it means
How strong is that tornado?
EF uses three-second gusts and the old F-scale fastest-quarter-mile winds, so the same rating number means different speeds. Ratings are estimated from damage.
The math
How to convert EF scale to F scale
EF ratings are gust bands: EF0 = 65–85 mph, EF1 = 86–110, EF2 = 111–135, EF3 = 136–165, EF4 = 166–200, EF5 over 200. TORRO: v = 2.365 × (T + 4)^1.5 m/s.
Example: EF4 EF scale = F3 F scale.
Every unit
That tornado on every scale
Tables
EF scale to F scale conversion table
| EF scale | F scale |
|---|---|
| EF0 EF scale | F0 F scale |
| EF1 EF scale | F1 F scale |
| EF2 EF scale | F1 F scale |
| EF3 EF scale | F2 F scale |
| EF4 EF scale | F3 F scale |
| EF5 EF scale | F3 F scale |
F scale to EF scale conversion table
| F scale | EF scale |
|---|---|
| F1 F scale | EF0 EF scale |
| F2 F scale | EF2 EF scale |
| F3 F scale | EF3 EF scale |
| F4 F scale | EF5 EF scale |
Quick answers
Quick answers
- How many F scale is EF1 EF scale?
- EF1 EF scale is F1 F scale.
- How many F scale is EF4 EF scale?
- EF4 EF scale is F3 F scale.
The units
About these units
Enhanced Fujita rating (EF scale)
EF0 to EF5, used in the US and Canada.
Fujita rating (1971) (F scale)
The original F0 to F5 scale.
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