Facebook has revealed that the company is raising the minimum wage of its US contract workers. The move is a reaction to the rising cost of living. The organization is facing extreme scrutiny over the treatment of lower-paid employees.

The minimum wage is increased to US$20 per hour from US$15 per hour. The company raised its minimum wage to US$20 per hour in the San Francisco Bay Area, New York and Washington DC and to US$18 per hour in Seattle.

Facebook last raised the minimum wage for contract workers in 2015 to US$15 per hour in an attempt to bridge the gap between the technology sector's elite and the lower-paid workers.

The company also said it will pay at least US$22 per hour for content reviewers in the Bay Area, New York City and Washington, DC, US$20 per hour to those living in Seattle and US$18 per hour in all other metro areas in the United States.

Last year, Amazon.com raised its minimum wage to US$15 an hour after facing criticism over poor pay and working conditions. The online retailer said at the time that it would lobby Washington for the federal minimum wage to be raised.

Walmart, the world's largest retailer and the largest US private sector employer, pays workers US$11 an hour at entry-level, while Target said in April it would raise US minimum wage to US$13 an hour.

According to reports, Silicon Valley is under pressure to close the income gap given California's high cost of living. The Office of Labor Standards Enforcement said it raised the minimum wage in San Francisco to US$15.59 per hour beginning July 1.