One in four customers who traded crypto so far in 2021 on the Robinhood Markets Inc. platform is a woman, said Christine Brown, chief operating officer of Robinhood Crypto. The firm said fewer women trade crypto on its platform than trade stocks and exchange-traded funds. Over the past two years, digital trading platform eToro Group Ltd. said the number of female crypto traders in the U.S. on its platform has jumped by half, to about 20% of all users in the U.S.

“Women should have an equal seat at the table when it comes to cryptocurrency investing,” Ms. Brown said.

Anthony Denier, chief executive at Webull Financial LLC, is surprised there aren’t more female crypto traders on the firm’s platform, owing in part to the availability of information about cryptocurrency investing online and women’s increased interest in managing their portfolios. About 21% of the crypto traders on the firm’s platform are female, a number he said is rising.

Erica Marie Wigley, a 49-year-old nurse, personal-development coach and meditation instructor in New York City, never thought she would invest in cryptocurrency, viewing it as a scam and a surefire way to lose money.

She changed her mind when one of her sorority sisters, whom she has known for about 30 years, encouraged her to buy a fraction of bitcoin through the Cash App in December.

In about four months, Ms. Wigley said her money has doubled, prompting her to text her three biological sisters to encourage them to invest in crypto too. While Ms. Wigley holds less than $2,000 of bitcoin, she is hoping to boost her investment over time by adding a small amount to her position every week or so.

“Crypto is a way for an everyday person like me to acquire some form of wealth,” she said.

To be sure, she doesn’t invest anything she can’t afford to lose.

“I understand I’m playing a game,” she said. While she watches bitcoin’s price daily, she doesn’t consider herself to be a day trader but rather an investor who is in it for the long haul because she doesn’t intend to sell.

In a report released Wednesday, the cryptocurrency exchange Gemini said 26% of current crypto holders in the U.S. are women, based on a survey of 3,000 U.S. adults, ages 18 to 65 with $40,000 or more in household income.

There are more women than men interested in getting into crypto soon: Women make up 53% of the “crypto curious” reporting interest about investing in the asset class, the company said. A quarter of these crypto-curious women surveyed are under the age of 35, and 25% are 55 or older, said Carolyn Vadino, a spokeswoman for Gemini.

Some women might be more likely than men to hold on to their crypto positions for the long term, according to a recent eToro study. They also seem to prefer different coins, with women, on average, holding more bitcoin and ether, and men holding more cardano and tron, eToro found. Cardano and tron aren’t nearly as widely traded as bitcoin and ether. Investors who are hoping to make a lot of money quickly might look to buy and sell coins that aren’t as frequently traded because they are more likely to get large gains soon in cheaper, more thinly traded assets.

“In general, women are long-term investors, less impulsive, and tend to hold on to their positions, which explains why they are over-indexed on bitcoin,” said

Guy Hirsch,

eToro’s U.S. managing director.

When it comes to bitcoin, Lisa Francoeur is in it for the long term.

The former software sales executive surprised herself when she became a cryptocurrency investor about a year ago. The 40-year-old Fort Lauderdale, Fla., resident became so passionate that she co-founded Crypto Tutors, an online tutoring business to help people learn to invest in cryptocurrency.

When the coin hit its recent high, she wasn’t surprised. Ms. Francoeur said most of the five figures she has invested in cryptocurrency is in bitcoin.

And while she is holding on to her bitcoin position, she is far more inclined to trade less-known coins she owns such as fantom because she feels she is more likely to make a quick return and has less to lose.

But her enthusiasm for crypto hasn’t caused her to take her eye off the sector’s riskiness. She said it is important not to leave too much of a portfolio in coins that have in the past been subject to large, single-day declines.

“It’s smart to realize your gains when you can,” she said.

—Caitlin McCabe contributed to this article.

Write to Veronica Dagher at veronica.dagher@wsj.com