Usain Bolt’s top speed during his 100-metre world-record run was 44.72 km/h. He reached this peak between the 60- and 80-metre marks while running 9.58 seconds at the 2009 World Championships in Berlin.
The figure comes from a 20-metre split completed in about 1.61 seconds, producing an average speed of 12.42 metres per second. It is therefore a measured segment speed, not Bolt’s average speed for the entire race. His overall average was lower because he had to accelerate from the starting blocks and slightly slowed near the finish.
Bolt’s 9.58-second performance, recorded on 16 August 2009, remains the men’s 100-metre world record. The often-repeated 44.72 km/h figure is sometimes mistakenly described as the speed he maintained throughout the race; it was his fastest measured section. His acceleration, extraordinary stride length and ability to sustain top speed helped separate him from the field.