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Brian Jacobson had been using online brokerages to invest for retirement since he was 18, but a decade later, when he’d bought a home and had a baby on the way, he started looking for a more efficient way to manage his financial arrangements.

A corporate finance professional, Jacobson didn’t see the value in paying the fees required by traditional financial planners, so last year he turned to Betterment. an online investment advisory service that offers personalized guidance based on clients’ objectives.

I’ve found it extraordinary, said Jacobson, 29, finance manager at Red Wing Shoe Co. in Minnesota. It’s so simple.

Betterment, based in New York City, is one of several relatively new online services offering investors automated financial advice and money management, often at a discount to traditional financial planners. The field includes firms such as Wealthfront. Personal Capital. FutureAdvisor. Hedgeable and Covestor.

These services often target the young and tech-savvy, catching them just as they are getting serious about investing.

According to founder and CEO Jonathan Stein. the typical Betterment customer is a professional who’s had a change, such as a marriage or major promotion, that makes money more significant.

Most clients at Palo Alto, Calif. -based Wealthfront are younger than 40, members of a generation that values transparency and trusts technology, said Chief Operating Officer Adam Nash. The average client has more than $80,000 at the firm, he said. The site offers low-cost, diversified investment management based on an investor’s age and risk tolerance.

We’ve taken a lot of the things that wealth managers do for the very wealthy and put it into software [for everyone], Nash said.

Some firms offer significant savings. While traditional financial advisors may charge a management fee of 1 percent to 2 percent, Betterment charges all-inclusive fees ranging from 0.35 percent for accounts with low balances to 0.15 percent for those with $100,000 or more, Stein said.

Wealthfront, which requires a minimum $5,000 to open an online investment account, manages the first $10,000 for free and charges a 0.25 percent annual advisory fee beyond that amount.

Demand appears to be strong. Betterment, which made its services available to the public in May 2010, had $165 million in assets under management at the end of March compared with $100 million in January.

The first $10 million took us a year, said Stein, who studied economics at Harvard and taught himself coding. Now it’s not uncommon to see $10 million in a week.

Wealthfront, launched in December 2011, has $185 million in assets under management and thousands of clients, Nash said.

Investors are hardly abandoning human financial planners, though.

Fairfax, Va.-based Edelman Financial Services launched an automated service in January. Edelman Online has 500 clients, $6 million funded and $10 million in transition—a fraction of the firm’s total of 20,000 clients and $10 billion in assets under management, according to CEO Ric Edelman.

Edelman Online offers the same services and pricing to online and offline customers. Fees range from 2% for the first $150,000 to 0.50% for eight-figure accounts.

Edelman said he launched the service to serve clients who primarily want investment management, which can be automated. But, he said, there’s no substitute for the talent of a human financial advisor who can give thoughtful, effective and comprehensive advice by developing a working relationship with a client.

Though customers can speak with employees, these start-ups focus on the online experience, combining investment and technology know-how to deliver automated advice.

Rick Kahler, a fee-only certified financial planner in Rapid City, S.D. whose clients have an average net worth of $2 million, sees room for new entrants in a field that tends to cater to the affluent.With most Americans living month-to-month, the average person would be way ahead using something like this, Kahler said.