The $1 million gift is part of a longer-term pledge by the six to "donate at least half of all income from our venture capital careers to philanthropic causes during our lifetimes."
The six are Netscape co-founder Marc Andreessen and general partners Ben Horowitz, John O'Farrell, Jeff Jordan, Scott Weiss and Peter Levine.
Along with their spouses, they hope their giving "can, over time, make the world a better place," they said in an April 25 statement.
"We are fortunate to work with some of the best entrepreneurs and technologists in the world and in the process help create great and valuable companies," they said.
"That activity, done well over decades, can generate a lot of money that can then be productively deployed philanthropically back into the society that makes it all possible."
The local nonprofits immediately benefiting from the Andreessen Horowitz gift are Santa Clara-based Via Services, serving children with special needs; the Ecumenical Hunger Program of East Palo Alto; Second Harvest Food Bank serving Santa Clara and San Mateo counties; Fresh Lifelines for Youth, a Milpitas-based nonprofit that works with at-risk teens; Canopy of Palo Alto, dedicated to planting and preserving trees in Palo Alto, East Palo Alto and surrounding communities; and The Shelter Network, an agency serving the homeless on the San Francisco Peninsula.
Canopy Executive Director Catherine Martineau said the approximately $170,000 gift is the largest in the agency's history.
It was designated by Andreessen Horowitz partner Peter Levine and his wife, Martha Blackwell, a former Canopy board member.
"Our family's passion for the environment and my specific interest in trees, along with our familiarity with the important work Canopy does in the community, guided our choice for this first round," Blackwell said.
Martineau said Canopy will use the gift to "pursue innovative education programs.
"Canopy is honored and grateful to receive this large gift and to be part of a group of leading organizations that do vital work in the community," she said.
Andreessen is the husband of local philanthropist Laura Arrillaga-Andreessen, author of the 2011 book "Giving 2.0: Transform Your Giving and Our World," which suggests ways to increase the effectiveness of charitable giving "of all forms and sizes."