SHENZHEN • Chinese online retail behemoth Alibaba posted record sales of 120.7 billion yuan (S$25.1 billion) during the Singles' Day festival, though the gala shopping day saw growth slow against the backdrop of an economy expanding at its slowest pace in a quarter- century.

The figure amounted to 68.2 per cent of the 177 billion yuan rung up by China's 16 biggest e-commerce sites, according to data provider Syntun.

On Alibaba's platforms, the best-selling items of the 24-hour event on Friday included Apple iPhones, Nike and Adidas gear and Haier appliances, the company said on its official blog.

Total sales on Alibaba Group Holding's platforms marked a 32 per cent rise from last year's 91.2 billion yuan turnover, but the increase was significantly lower than the 60 per cent rise logged last year, amid a more saturated domestic online retail market, a weaker economy and sluggish personal income growth hitting consumers' wallets.

Alibaba's United States-traded shares fell 2.7 per cent at 11.27am on Friday in New York.

Alibaba chairman Jack Ma played down the importance of the final figure in a speech shortly before midnight, echoing other executives who spoke during the day.

"(Singles' Day) is not about a number only," said Mr Ma. "When volumes started to grow a little less fast, I actually became more relaxed." He added: "We don't want to cause the entire logistics system to collapse."

China's No. 2 e-commerce giant JD.com, which focuses more on electronics, said its sales total - which it did not specify - also surpassed last year's figure.

Singles' Day was invented by college students in the 1990s as a counter to Valentine's Day. Written numerically, Nov 11 is reminiscent of "bare branches", a local expression for bachelors and spinsters.

Alibaba pioneered the annual Singles' Day-themed shopping spree in 2009 and has since transformed it into a social phenomenon, replicated by rivals such as JD.com and now involving thousands of marquee labels worldwide.

It now offers a benchmark for Alibaba's performance and an insight into China's swing to online shopping, especially by smartphone, to the detriment of brick- and-mortar stores.

Around 82 per cent of total sales were via mobile devices, up strongly from last year. The day itself is a double-edged sword for many. Couriers and packaging firms say low prices and steep competition meant profit margins were slim despite large sales volumes.

Retailers are also starting to feel the pinch. The average cost per order shrank to 184 yuan from approximately 194 yuan last year, according to the unaudited metrics released by Alibaba.

Cut-throat competition for customers has also caused concern over false advertising and massaged statistics. Last week, China's business regulator advised mainland online shopping platforms to guard against suspect sales tactics.

Analysts said the event is key to Alibaba.

The day's turnover was only "a very small fraction of its total annual sales", independent e-commerce analyst Li Chengdong said, but it was "a confidence index for the firm".

"If they do well in this, it is a boost to investors' confidence," he said.

REUTERS, BLOOMBERG, AGENCE FRANCE-PRESSE, XINHUA