Tornado Scale Calculator (Enhanced Fujita Scale)
Determine the EF rating of a tornado from estimated wind speed.
See damage descriptions, frequency statistics, and historical comparisons.
The Enhanced Fujita (EF) Scale The EF Scale replaced the original Fujita Scale on February 1, 2007 in the United States. It rates tornadoes from EF0 to EF5 based on the damage they cause, which is then correlated to estimated wind speeds. Unlike the Saffir-Simpson hurricane scale, tornado ratings are assigned AFTER the tornado passes based on damage surveys, not from direct wind measurements.
EF Scale Ratings EF0 (65-85 mph / 105-137 km/h): Light damage. Peels surface off some roofs, some damage to gutters, vinyl siding. Branches broken, shallow-rooted trees pushed over. About 53% of all tornadoes are rated EF0. EF1 (86-110 mph / 138-177 km/h): Moderate damage. Roofs severely stripped, mobile homes overturned or badly damaged, exterior doors lost. About 32% of all tornadoes.
EF2 (111-135 mph / 178-217 km/h): Considerable damage. Roofs torn off well-constructed houses, foundations of frame homes shifted, large trees snapped or uprooted, cars lifted off the ground. About 10% of tornadoes. EF3 (136-165 mph / 218-266 km/h): Severe damage. Entire stories of well-constructed houses destroyed, severe damage to large buildings, heavy cars thrown. About 4% of tornadoes.
EF4 (166-200 mph / 267-322 km/h): Devastating damage. Well-constructed houses completely leveled, cars thrown considerable distances, structures with weak foundations blown away. About 1% of tornadoes. EF5 (200+ mph / 322+ km/h): Incredible damage. Strong frame houses swept clean off foundations, automobile-sized missiles fly through the air over 100 meters, steel-reinforced concrete structures critically damaged. Less than 0.1% of tornadoes.
Original Fujita Scale Created by Ted Fujita (known as “Mr. Tornado”) in 1971 at the University of Chicago in the United States. Fujita developed the scale after years of aerial surveys of tornado damage. The original F-Scale was replaced by the EF-Scale because it better correlates wind speeds with specific types of structural damage using 28 damage indicators.
Tornado Facts The United States experiences about 1,200 tornadoes per year — more than any other country. Tornado Alley (central US) sees the highest concentration. The deadliest US tornado was the Tri-State Tornado of 1925, which traveled 219 miles across Missouri, Illinois, and Indiana, killing 695 people.