As many as 800 million workers worldwide may lose their jobs to robots and automation by 2030, equivalent to over a fifth of the global workforce today, a new report covering 46 nations and over 800 occupations by the research arm of McKinsey & Co projects.
According to the consulting company, both developed and emerging countries will be impacted.
The worst hit will be machine operators, fast-food workers and back-office employees if automation were to spread quickly through the workplace.
''We're all going to have to change and learn how to do new things over time,'' Michael Chui, a San Francisco-based partner at the institute, said in an interview, Bloomberg reported.
In the US, 39 million to 73 million jobs could be destroyed, but about 20 million of those displaced workers could be easily shifted into similar occupations, though they may take on slightly different tasks, according to the report.
This would require 16 million to 54 million workers or as much as a third of the US workforce to be retrained for entirely new occupations.
Jobs that would be least affected from the change involve managing people, high-level expertise, which include engineers, scientists, health care providers, educators and IT professionals, as also gardeners, plumbers and elder care providers.
High-wage workers would therefore be expected to be less affected by the sweeping changes as they have skills that cannot be replaced by machines.
Low-wage jobs could also see an increase partly because they cost employers less and so are often not worth supplanting with technology.
Also middle-wage jobs will continue to decline widening the divide between wealthy and low-income households, the report says.
To remain viable, workers would need to embrace retraining in different fields, but they would need to helped by companies over what could be could be a rocky transition.
"The model where people go to school for the first 20 years of life and work for the next 40 or 50 years is broken," Susan Lund, a partner for the McKinsey Global Institute and co-author of the report, told CNN Tech.
"We're going to have to think about learning and training throughout the course of your career."
The biggest challenge, Lund says, would be retraining millions of mid-career workers.
Governments and businesses already had already fallen short in the retraining of workers who lost jobs in the recession of 2007 to 2009.
''The big question isn't, 'Will there be jobs?' '' USA Today quoted Lund. ''The big question is, 'Will people who lost jobs be able to get new ones?' ''
Workers who are willing to develop new skills should be able to find new jobs.
"The dire predictions that robots are taking our jobs are overblown," Lund said, CNN Money reported. "Yes, work will be automated, [but] there will be enough jobs for everyone in most areas."
According to the report, ''there are few precedents in which societies have successfully retrained such large numbers of people.''
At the same time the authors acknowledge that the adoption of automation could be far slower than they anticipate, forcing less 10 million workers globally to switch occupations.