Going beyond previous estimates, market research firm IDC said it expects that tablet computers will outsell laptops this year.
Tablets were already on pace to beat sales of desktop computers: By 2015, IDC said, tablets will have more market share than the entire traditional PC market.
"Tablets surpassing portables in 2013, and total PCs in 2015, marks a significant change in consumer attitudes about compute devices and the applications and ecosystems that power them," said Ryan Reith, program manager for IDC's Mobility Trackers.
Reith said PCs will remain important to business users, but as many companies switch from clipboards and paper to tablets, the tablet market is expected to grow even faster.
For regular consumers, Reith said, tablets are proving to be suitable replacements for basics, such as checking email and browsing the Web.
The slowdown in PC sales is partially attributed to consumers delaying purchases of traditional computers until absolutely necessary while instead choosing to try out tablets.
About one in 22 people worldwide will buy a PC this year compared with one in 31 for tablets, IDC reported, but by 2015, there will be more tablet-buyers.
IDC also noted that 55% of tablets sold this year will have a screen size of less than 8 inches, making the small form a majority for the first time. Apple kicked off the tablet market with a 9.7-inch screen iPad. Last year, the company introduced the iPad Mini to compete with a slate of 7-inch Android tablets from competitors such as Samsung.
IDC projected that the market share for tablets between 8 inches and 11 inches in size will drop by half, to 37%, by 2017.