US consumers spent a record $3.3 billion online on Black Friday, scooping up everything from Lego sets to Apple iPads, according to Adobe Systems Inc.

Two-day sales starting on Thanksgiving totaled $5.3 billion, marking an 18 percent increase from a year earlier, Adobe said in a statement. Spending via mobile devices on Friday increased 33 percent to an all-time high of $1.2 billion.

The surge in online shopping has taken a toll on bricks-and-mortar stores. In-store visits dropped a combined 1 percent during the two days from a year earlier, said ShopperTrak, a retail data provider, in a separate statement.

Adobe, the design software company based in San Jose, California, said the most popular items include Lego A/S building sets, Razor electric scooters, flying drones, Mattel Inc Barbie dolls, Samsung Electronics Co 4K television sets and Apple Inc iPads and MacBooks.

"Shoppers hit the buy button at unprecedented levels as conversion rates were up nearly a full percent across all devices in the evening hours on Black Friday," Tamara Gaffney, an analyst at Adobe Digital Insights, said in the statement.

Adobe said it tracks 80 percent of all online transactions at the top 100 US retailers.

The National Retail Federation has projected that about 137.4 million consumers will make purchases in stores or online over the four-day weekend that started on Thanksgiving, marking the kickoff to the holiday shopping season in the country.

Bloomberg