More than $5m (£3m) has been donated to charity in six months through an application for Facebook and MySpace that allows users to fundraise and give through their online social networks, doubling the total raised in two years.

The Causes application has raised $10m (£6m) through 200,000 donors who have given to 26,000 groups since its launch in May 2007. The average donation was $25. The Birthday Wish feature, which allows users to nominate a charity to receive donations from their ‘friends’ as a birthday gift, has raised $1.4m.

Any Facebook or MySpace user can sign up to the Causes application through their profile.

Joe Green, co-founder and president of Causes, said in a post on its blog that the total amount donated online could mean clean drinking water for 50,000 people for 20 years.

“It is through the incredible dedication and commitment of all of our users and activists that we have gotten this far,” said Green. “Thank you for working with us to pursue the goal of creating lasting social and political movements around the world.  This is only the beginning!”

Facebook reached 250m users this month (July), up from 100m in August 2008. MySpace had around 125m users at the end of 2008, up from 100m in August 2006.