San Francisco ? Despite concerns that an ongoing credit crunch will put the pinch on consumers this holiday season, experts still expect shoppers to open their wallets online.

Holiday shopping on the Web is expected to top the $30 billion mark this year, according to a pair of forecasts. That would represent an increase of more than 20 percent from last year’s totals.

Signs have been encouraging so far. According to data from comScore, the first 18 days of November saw total online-retail spending reach above $7 billion – up 17 percent from the same period last year.

The market-research firm warned, however, that figures for the later part of the month “are likely to be better indicators of how the remainder of the season will play out.”

On Friday, consumers flocked to stores for traditional “Black Friday” sales, in which many retailers offered deep discounts on popular items to lure shoppers.

The turnout may lead to a strong “Cyber Monday” on Nov. 26. The term was coined on the theory that consumers returning to their offices on the Monday following Thanksgiving flock to Web sites to find items they were unable to get in stores over the weekend.

“Consumers will continue to shift more of their holiday gift spending from stores to sites this year,” Jeffrey Grau, of market-research firm eMarketer, wrote in a Nov. 15 report.

According to data from comScore, the first 18 days of November saw total online-retail spending reach above $7 billion – up 17 percent from the same period last year.

He said that the figures show the trend toward online shopping “will insulate retail e-commerce from the economic jitters expected to dampen retail industry sales during the critical months of November and December.”