Usain Bolt's fastest recorded speed occurred during his world record 100-meter sprint in 2009, where he completed the distance in 9.58 seconds. His average speed for that run was about 10.44 meters per second, which converts to approximately 37.58 kilometers per hour (23.35 miles per hour). However, his top speed during the race was even higher. At around 67 meters into the race in a 2011 measurement, Bolt reached a peak speed of about 43.99 kilometers per hour (27.33 miles per hour). Other measurements of his top peak speed during competition have been around 44.35 km/h (27.56 mph), which is considered the fastest speed a human has ever been recorded running.

In summary:

• World record 100m time: 9.58 seconds (2009)
• Average speed during that race: ~37.58 km/h (23.35 mph)
• Peak top speed reached: ~44 km/h (about 27.3 to 27.6 mph)

This makes Usain Bolt the fastest recorded human sprinter in history.