Women and men not only shop differently online — women also drive most e-commerce spending. Here’s how to target your best online customers.

Women have long been the nation’s buyers in chief, accounting for a whopping 85 percent of all consumer purchases. They now also account for nearly half of all purchases in traditionally male-dominated categories, such as cars, computers and consumer electronics.

As shopping on the Internet evolved from techie toys in the 1990s to consumer-based search services through the mid-2000s to the current multichannel powerhouses and mobile apps, it was only a matter of time before women flexed their economic muscle online, too.

Women are moving e-commerce markets

Today, women represent about half (49.8 percent) of all U.S. online users, according to “Women on the Web,” a June 2010 comScore global report. Yet women make more online purchases (61 percent) than men do and account for nearly $6 out of every $10 (58 percent) spent online.

As you might expect, women effortlessly rule in apparel and accessories (71 percent of dollars spent) as well as toys and hobbies (67 percent of dollars). More surprising, however, is that women dominate across online categories, including video games. Men spend more, though not by much, in only a few areas, such as computers, sports gear and event tickets. (The numbers suggest that men make fewer but bigger-ticket buys while women buy more often, spending less per order.)

“Our research helps illustrate just how massive an opportunity exists for marketing to women and the advantage of developing technology and products that speak to their needs and improve their lives,” said Linda Abraham, comScore’s chief marketing officer, when the report was released.

What’s influencing women’s online habits?

Recent innovations in local, mobile and social technologies have accelerated women’s online engagement, particularly in social networking activities.

For instance, women use their phones to “tweet” and “friend” 10 percent more than men do and, on average, send and receive 30 percent more monthly text messages, according to Nielsen 2010 data. Worldwide, comScore found that women average 5.5 hours per month on social networking sites, compared to men’s four hours.

In turn, women’s enthusiastic adoption of social media and growing online spending are fueling the rise of female-friendly portals, such as social shopping sites, group buying sites, limited-time flash sale sites and push-pull coupon aggregators.

Such new options give consumers “the capacity to buy or come closer to purchase when excitement about a product or service is highest,” says Nita Rollins, business strategist at digital marketing agency Resource Interactive. It’s likely that women will be quicker than men to adopt what the agency dubs “everywhere commerce,” a new landscape in which “all the world’s a store.”

In the near future, predicts Rollins, value for online women will come “in the form of timely, personalized, even geo-aware offers and recommendations [what are known as ‘triggered’ touch points], auto-replenishment programs — no more running out of shampoo or pet food — and better product information, ranging from video tutorials to consumer-generated opinions and reviews.”

What women want online

If you’re ready to gear your sites toward women, here are more findings worth keeping in mind:

- Gender stereotypes: The Venus/Mars divide has blurred since early studies concluded that “women are on a mission” and “men won’t research.” Reports comScore: “Women are just as likely [as men] to manage their money online, and moms and grandmothers have emerged as online gamers along with high school- and college-aged boys.”

- Retail preferences: Women and men choose different kinds of retailers. Men gravitate toward pure-play retailers (Amazon.com, Netflix) while women are equally drawn to multichannel retailers (Best Buy, Target) as well as Web-only merchants.

- Search engine marketing strategies: “Women are more likely to use long-tail keywords when searching for an item whereas men will just type in one or two words,” says Teran Dale, a pay-per-click marketing expert. “Knowing this can not only save you money on clicks, but also increase sales.”

-Email marketing: Female-focused subject lines and text generate much higher CTRs (click-through rates) than generic messaging, reports Heather Bonura, director of brand strategy at Listrak, a Lititz, Pennsylvania-based email marketing firm.

For instance, a Listrak woman-friendly email campaign for footwear maker Birkenstock Central generated a remarkable 9.09 percent conversion rate, compared to its previous 3.63 percent average. Listrak’s holiday stemware campaign did even better, achieving a stunning 30 percent conversion rate, says Bonura, “by combining gender-specific messaging and behavioral targeting” — that is, “targeting groups who had previously purchased or browsed similar stemware.”

Leverage social media marketing

If you’re inclined to shift marketing gears toward women, but are wary about investing resources in online sales, consider this: Yes, the pace of online sales has slowed, owing to both a maturing market and the economy. But Forrester Research still projects that e-commerce will amount to 8 percent of total U.S. retail sales, or $249 billion, by 2014.

More important, concludes Forrester, “online combined with ‘Web-influenced sales’ will be a staggering 53 percent of total retail sales by 2014.”

In other words, the key is to integrate marketing channels as the online influence of women grows. That works best, says Randy Herbertson — president of Wonder, a New York City-based branding agency — when you leverage content from multiple social networking services “to create recency, relevancy and advocacy.”

By harnessing that power, you’re likely to both attract women and boost sales.