Started in 2006 by an Egyptian national, the site in English is one of a handful of specifically Muslim communities developing a niche in a growing market. Others include Mecca.com and Islamicaweb.com.
Ahmadzai, who lives in Finland but is originally from Afghanistan, has been part of Muxlim for two years. She found it easier than on Facebook to make friends and join groups, and likes the site's culturally sympathetic sounding-board.
We all share the same ideology, even if you're non-Muslim or even atheist... the fact that you are interested in knowing about Islam or knowing how Muslims are, it kind of brings the entire site into one, she told Reuters at a cafe in a Helsinki mall.
Muxlim is tiny: in Britain alone, it registered just 22,000 unique visitors in January versus 22 million for Facebook according to internet database ComScore.
ComScore does not register traffic for Mecca.com and Islamicaweb.com. Mecca.com says it has 50,000 users, while a member search on Islamicaweb.com returns 9,748 users.
The sites all feature videos, news, images, blogs and chat related to Muslim culture and Islam.
Ahmadzai's real-life friend Bahmanpour, a Finnish-Iranian who joined Muxlim recently, said she has 52 friends on the site mostly from the United States and Britain, and likes it because it involves Muslims from the conservative to the very liberal.
She has on her profile three images of herself in a veil taken by a professional photographer: in one she wears make-up to imitate a superhero.
This actually caused quite a discussion. Quite a few people told me I emphasize myself too much in the pictures, Bahmanpour said. Basically it just shows how different we all are.
As registered users of Muxlim, the girls are connected to about 150,000 users worldwide who chat, share content, participate in polls and read news items from Muslim countries.
They can also create their own virtual characters -- avatars -- and interact with others.
Socially conservative Muslims with more rigorous rules for interacting with the opposite gender often have no problems communicating with one another online, said American-Pakistani journalist and blogger Ali Eteraz.
Eteraz said he has seen such sites pick up a large number of members at launch, but then growth slows down significantly: much depends on marketing budgets.
Muxlim's 24-year-old creator, Mohamed El-Fatatry, says the total number of site visitors has accelerated to 1.5 million monthly from 100,000 18 months ago.
The figure is only a humble two percent of the world's online Muslim population, said El-Fatatry, who came from the United Arab Emirates to Finland to study in 2004, lured by the Nordic country's reputation as a hotbed of tech innovation.
He said the site, which generates income from advertising and selling downloadable content, aims to be profitable by the end of next year and targets 10 million visitors monthly.
His strategy has been first to enter countries with Muslim minorities: about 60 percent of Muxlim users are currently in North America and Europe. About three percent are non-Muslims, and more than half are female.
A year after startup, in 2007, Muxlim received a $2 million investment from venture capital firm Rite Internet Ventures.
They had good traffic numbers, it was appreciated by its users, and we thought that this target group -- a target group with buying power -- had been neglected, said Christoffer Hagglund, the Swedish firm's chief executive.
Muxlim is now seeking second-round financing, and El-Fatatry plans to expand the site by partnering with brands wanting to tap into the Muslim community. He cited a 2007 study from advertising agency JWT that estimated the disposable annual income of Muslims in the United States alone at $170 billion.
Muxlim first started as MuslimSpace, but El-Fatatry renamed it in an oblique reference to Linux, the open-source computer operating system, after a Finnish newspaper compared his work to that of Linux creator Linus Torvalds, a Finn.
(At the time) you found many sites that offered core religious services or marriage services, and a lot of political analysis websites, he said.
None of those were really what I was looking for. I wanted a site where I can share content about the fashion I am interested in, the music I listen to or the movies I watch.
Muxlim does not have a strict editorial policy, but does monitor traffic to avoid vulgar language or racist or sexually explicit images, El-Fatatry said.
Where else are you going to find a niche market that is a fifth of the global population? he said.
Journalist Eteraz said a site in English could be attractive to Muslims in the West, especially in the United States, Canada and the United Kingdom, and a younger crowd from Muslim-majority countries.
For a Web site that is using a broad principle -- Islam -- to market itself, having the most global language is better than going in Arabic or some other regional language, he said.
Ahmadzai and Bahmanpour said they use Muxlim because of the friends they have made and discussions they have.
Ahmadzai, who has a Japanese anime image on her profile, says in some discussions people say she is too open about things. She cites a conversation about a newlywed wife's right not to not sleep with her husband until she is ready:
I believe discussions like these are exactly the reason why you should stay online. If we don't discuss, we won't learn.
(Editing by Sara Ledwith)