As part of a plea deal at Los Angeles County Superior Court, the 19-year-old avoids a jail term.
He will be on probation for five years and has been ordered to do six months of community service.
He must also attend courses on domestic violence and stay at least 50 yards from Rihanna, 21.
Speaking on her behalf, lawyer Donald Etra said the verdict was a 'fair and just resolution'.
Chris was arrested hours before the Grammys on 8 February.
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