Adobe predicts huge increase online sales during upcoming festival with sales growing 18% to $2bn over 2011.

The company has also predicted there will be strong purchasing activity over mobile devices, with mobile representing 21% of total online sales this holiday, registering 110% increase over last year.

Cyber Monday or November 26 would be the biggest online shopping day of the year in the US, while Black Friday or November 23 is expected to be the second largest online sales day in 2012.

According to the forecast, on November 23, retailers are expected to see their sales increase 12% over last year.

During Green Monday or on December 10, online sales volume is expected to grow 7% over last year, while on that day the report predicts that online retailer can expect sales increase of nearly 150% compared to an average day throughout the year.

On Free Shipping Day or December 17, online sales is also expected to grow by 12% year-over-year, as merchants offer free shipping online with guaranteed delivery by Christmas Eve.

Out of the total volume of sales expected over mobile phones, 13.5% of them will comprise tablets, which will be double that of smartphones 6.5% while and other devices such as e-readers will comprise 1%.

On Black Friday, consumers are expected to use their tablets and phones to shop more than any other day of the year with 24% growth in online visits predicted to be through customers’ mobile phones.

During the upcoming holiday season, mobile shopping is projected to increase in Europe and the report predicts that sales from mobile devices expected to double from 6% to 12%, year-over-year.

Adobe said that the projection are based on analysis of more than 150 billion online visits to over 500 retail websites in the US. and Europe over the past six years.

An earlier report, IMRG Capgemini eRetail Sales Index revealed that, consumers will spend nearly £1bn through their mobile devices in the run up to Christmas, up an estimated 15% on last year’s figure.