 "Fighter" received mostly positive reviews from music critics, who praised Aguilera's vocals and the song's empowering lyrics. The single peaked at number 20 on the US Billboard Hot 100 and was certified gold by the Recording Industry Association of America (RIAA). As of September 2014, "Fighter" has sold 1.184 million copies in the United States. Elsewhere, the song reached the top ten of several national music charts, including those in the United Kingdom, Canada, Australia, and the Netherlands.
