overestimate

Meanings

Noun

• an appraisal that is too high
• a calculation that results in an estimate that is too high

Verb

• make too high an estimate of
  • "He overestimated his own powers"
• assign too high a value to

Synonyms

overappraisal, overestimation, overrate, overrating, overreckoning, overvaluation, overvalue

Antonyms

underestimate, undervalue