Xiao Ya, a 21-year-old model for Taobao.com, during a photo shoot at a studio in Chengdu, capital of Sichuan province. Popular commercial models are said to be able to make 150 yuan ($24.5) per outfit they try on. [Lyu Jia / China Daily]

He Ningning can find herself changing into more than 200 outfits a day in her role as a model for Taobao.com, China's largest online shopping site.

On her busiest days she can work for more than 15 hours. But she is not alone.

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Online modeling is a growing opportunity for aspiring young models like her, as China's e-commerce shopping sector becomes increasingly frenzied and sophisticated with companies of all sizes employing the services of thousands of models to promote their stores.

November was often considered a low season for shopping - but with the advent of arguably the country's biggest shopping day of the year, "Singles' Day" on November 11, He Ningning said her assignments book was packed last month as shops prepared for the sales campaign.

"Merchants pay particular attention to photos shot for this sales day. And increasingly, they are choosing to spend on booking more popular models, creating more exquisite settings, and using better photographers," she said.

Popular commercial models can make up to 150 yuan ($24.5) per outfit they try on, He said, meaning a typical day's work in the run up to the Singles' Day promotion can be worth many thousands of yuan in income.

"I'm happy with the job because of the good earnings. It also helps me become more confident about my abilities and gives me experience," He said.

Taobao.com, founded in 2003 by Alibaba Group Holding Ltd, China's largest e-commerce company, boasted 230 million active users last year and has captured a leading market share of China's booming online shopping market.

Internet shopping has made it possible for some women and men without any professional modeling experience to make high-profile livings.

The requirements involved are often very different for online models than they are for those working on luxury brands, however - they need to look homely and approachable, to appeal to a less sophisticated and often lower-spending and diverse customer base.

Taobao.com's online stores are believed to employ around 40,000 models who helped generate gross revenue of more than 3 billion yuan on online sales last year, according to Alibaba.

They also helped boost the sales of thousands of online merchants selling goods from across a host of different sectors. The models themselves are signed up by thousands of design and photographic agencies and other outsourcing service organizations. As a result, more than 1 billion yuan worth of business were created.

Some experts, however, are warning the modeling sector is becoming saturated with too many young men and women such as He, and of those 40,000 only around 50 can ever expect to become genuinely well known.

With so many involved, they say, the lack of training also means many will never attain the level of professionalism they need to make it really big, in what has always been considered a cutthroat business.