The value of digital music sales in the first half of 2006 rose 106 per cent to $945 million, according to music industry association, the IFPI.
Globally, digital sales now account for 11 per cent of the total recorded music market worldwide, up from 5.5 per cent in December 2005, the IFPI added.
In the US, 18 per cent of recorded music sales now being made through digital channels. Digital music sales climbed 84 per cent in the first six months of 2006.
Digital music also accounts for a significant part of the overall market in South Korea (51 per cent), Japan (11 per cent), Italy (9 per cent) and the UK (8 per cent).
The explosion in digital music services has seen online and mobile music sales grow from $134 million in the first half of 2004 to $945 million in the first half of 2006.
In Japan, Italy and Spain mobile dominates the digital market, accounting for 85 per cent, 76 per cent and 78 per cent of overall sales respectively.
Online downloading is more prominent in markets such as the UK, Germany and the US, where online sales account for 70 per cent, 69 per cent and 64 per cent of digital sales respectively.
Physical music sales declined in the first half period, down by ten per cent worldwide. This led to total music sales falling by four per cent in the period to $8.4 billion in trade values.