• 79% of female investors say they are confident that they're on track with their retirement savings. However, just a third of women overall view themselves as investors or feel confident making investment decisions.
• There are some things you can do to build your investing confidence.
• Overconfidence, however, can be problematic as an investor.

For women who are investing, confidence generally runs high.

It's getting over the initial hump that appears to be the challenge.

A full 79% of women investors in the U.S. say they are confident that they'll achieve their retirement goals using their current investment approach, according to a survey from social investing app eToro. Yet among women overall, just a third even consider themselves investors or feel confident in their ability to make investment decisions, research from Fidelity Investments shows.

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"If you don't feel confident, you're not going to invest," said Callie Cox, U.S. analyst at eToro.

For most workers, putting at least a portion of their money in the stock market through a 401(k) plan is the best way to save for retirement, generally speaking. Otherwise, inflation over time can erode the value of money held as cash or in low-risk, low-yielding investments.

"Unfortunately, women who don't invest a good portion of their savings will take the chance that they won't have enough money to last through retirement, or their standard of living in retirement will be lower than it is while earning," said Cathy Curtis, a certified financial planner and founder of Curtis Financial Planning in Oakland, California.

If you're among those who stay on the sidelines due to fear of making a mistake, it's worth knowing that women investors outperform their male counterparts over time when it comes to returns on their investments, according to Fidelity's research.

This is largely due to women's buy-and-hold strategy — i.e., investing for the long-term — instead of frequently trading or panic selling during market pullbacks.

"Women are hard-wired to be better investors," said Randy Bruns, a CFP and founder of Model Wealth in Naperville, Illinois. "Women are far better at following recommendations and tuning out the news than men."

And, your investments generally should reflect your risk tolerance — which is a combination of how long until you need to tap the money and how well you can stomach volatility in stock prices. So, for example, if you have several decades until you retire, the ups and downs of the market should matter little to you because your portfolio has plenty of time to recover.

Nevertheless, it's not uncommon to feel nervous about making investing decisions, advisors say. One key to overcoming that trepidation is simply learning what it's all about.

"Even studying a simple chart of the long-term returns of investing in the S&P 500 [Index] tells a story," Curtis said. "Yes, the line is bumpy, but it is always going up over time."

Tied to that is the importance of taking a long-term view of the money you invest, she said.

"Anyone — even a confident investor — could get anxious if they focus on the short-term swings of the stock market," Curtis said.

While having enough confidence to invest is important, too much of it can be problematic.

For instance, overconfidence can cause an investor to plow too much money in one sector of the market — say, technology stocks — instead of spreading money across various industries, company sizes and locations (i.e., both U.S. and international stocks), Curtis said. Bonds also can play an important role in making sure your eggs aren't all in one basket, so to speak.

"The trader's mentality may work for some in the short-term, but for most of us … it's better to stay invested in a diversified portfolio," Curtis said.

You also may be able to tap into online groups of women investors, which also may help build your confidence. If you go this route, be sure not to fall victim to groupthink — that is, finding yourself going with the crowd and making investment decisions based on what everyone else in the community is doing.

"It's empowering, helps with information flow and building confidence, but you have to be careful of falling into groupthink," said Cox, at eToro.