Sonic's speed varies widely depending on the source and context:
- In classic Sonic games, Sonic's top speed on flat ground is about 8.43 meters per second (about 30.3 km/h or 18.9 mph), which is roughly the speed of a very fast human runner.
- In more modern or expanded Sonic media like Sonic Unleashed, Sonic is said to run faster than the speed of sound, with some gameplay references putting his speed as high as 999 mph at peak in-game speedometers.
- According to some game manuals and lore, Sonic can reach speeds approaching or exceeding the speed of light (about 186,000 miles per second). For example, in Sonic Unleashed's SPD meter, Sonic's top speed is calculated to be over 6 billion mph, more than nine times the speed of light.
- In Sonic comics and fan measurements, Sonic's sustained running speed is about 767 mph, and his maximum burst speed can reach the speed of light, but only momentarily.
- Super Sonic, a powered-up form of Sonic, is portrayed as even faster, capable of traveling distances at cosmic speeds far exceeding the speed of light.
In summary, Sonic's speed ranges from a very fast runner in his early classic game form to virtually light-speed or even beyond in modern games, comics, and lore. The most "official" in-game numbers point to speeds over the sound barrier, while the extended universe often attributes light-speed or greater qualities to him. Thus, Sonic is typically described as being able to run anywhere from around 30 km/h in early games to over 186,000 miles per second or more in later lore and official media.
