Sonic's SPD clocked in Cool Edge.

SPD is a game mechanic that appears in the PlayStation 3/Xbox 360 version of Sonic Unleashed. It is a speed measurement used to rate Sonic's velocity in daytime Action Stages.


Whenever Sonic passes a Star Post during daytime Action Stages, the checkpoint will clock how fast Sonic is going and measure his velocity in SPD.

The value of SPD in measurement is never elaborated in the game, but it has been calculated that Sonic's top speed in gameplay is 179 mph.[citation needed]


  • One mph is calculated to be roughly equal to approximately 8SPD.[citation needed]
  • It is unknown if "SPD" is an abbreviation of the word "speed", a recurring measurement for velocity in the Sonic Riders series, or an acronym.

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