November and December have been good for online retailers as holiday shoppers have spent 12% more than last year.

Buyers have dropped more than $27 billion online since November.

Experts say there are a few things they can credit with the surge in online shopping: more people looking to the web, a better overall shopping season than the last few years, and free shipping.

According to research firm Com-Score, more than half this holiday season's transactions have come with a free shipping offer. More than 1,500 online merchants included the deal. In the November 1 through December 17 period, which these numbers account for, four individual days surpassed $900 million mark. That included "Green Monday" on December 13 with $954 million and "Free Shipping Day," December 17, with $942 million.

So far, clothing and jewelry have been the big items this year. Experts say that's good news as consumers have more discretionary cash than in recent years to spend on those luxury items.

Retail experts say another bit of good news with this spending spike is that it's happening even though retailers aren't enticing shoppers with the deep, deep cuts we saw the last 2 years.

Last week alone, retail experts say shoppers spent $5.2 billion.